JP2001318724A - Voltage generation system, voltage generation circuit, voltage regulator and portable terminal equipment using them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a voltage provided with the high-speed transition responsiveness of an output voltage and applicable to a system requiring large current supply capacity without sacrificing a stationary leakage current. SOLUTION: An output transistor and a high resistor are serially connected between power supply terminals and a constant-voltage-controlled output voltage is generated from a connection point to a load. In the voltage generation, a low input resistance constant voltage generation means for generating a constant voltage equal to the target value of the output voltage by low input resistance is provided, and when a difference is generated between the voltage of the low input resistance constant voltage generation means and the output voltage (or a divided voltage), the connection point and the low input resistance constant voltage generation means are connected by a switch.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC-based voltage generating circuit for outputting a constant voltage, a voltage regulator,
And a mobile terminal device using the same.

[0002]

2. Description of the Related Art Conventionally, a voltage generating circuit for outputting a constant voltage serving as a reference voltage to a load circuit and a voltage regulator for outputting a voltage adjusted to a predetermined value have been widely used, for example, as a power supply for portable terminal equipment. Have been.

FIG. 11 shows a general configuration example of a conventional reference voltage generating circuit for generating a reference voltage used for internal step-down of a semiconductor memory, for example. In FIG. 11, the reference voltage generation circuit 1
10 is an error amplifier 1, a P-type output transistor Q1,
It is configured by a resistor R1 and receives an internal reference voltage Vref as a voltage command value from an internal reference voltage circuit 8 as a reference voltage generation source, and outputs an output voltage Vout to a load circuit 9 including a capacitor C.

The gate of the output transistor Q1 is connected to the output of the error amplifier 1, the source is connected to the power supply terminal, the drain is grounded to the ground via the resistor R1, and
It is connected to the non-inverting input terminal of the error amplifier 1 while being connected to the load circuit 9 as an output terminal. Further, the internal reference voltage Vref is input from the internal reference voltage circuit 8 to the inverting input terminal of the error amplifier 1.

In this configuration, the error amplifier 1 compares the drain voltage Vq1d of the output transistor Q1 with the internal reference voltage Vref.
The output voltage Vout is made constant by raising and lowering the gate potential of the transistor 1 and controlling the on-resistance of the transistor Q1. That is, Vout = Vref.

On the other hand, the configuration of a reference voltage generating circuit (JP-A-5-114291) with improved noise immunity is shown in FIG.
It is shown in FIG. In FIG. 12, two types of internal reference voltages Vref
1, an internal reference voltage circuit 8 'for outputting Vref2, a reference voltage generation circuit 120, and a load circuit 9 including a capacitor C. The reference voltage generation circuit 120 includes error amplifiers 1 and 2, a P-type output transistor Q1 having different driving capabilities. , Q2 and resistor R
1 is comprised. The internal reference voltage circuit 8 'outputs an internal reference voltage Vref2 (= 3.0 V) and an internal reference voltage Vref1 (= 2.7 V) slightly lower than the internal reference voltage Vref2,
The signals are input to the inverting input terminals of the error amplifiers 1 and 2, respectively.
The gate of the output transistor Q1 is connected to the output of the error amplifier 1, the gate of the output transistor Q2 is connected to the output of the error amplifier 2, and the sources of both transistors are connected to the power supply terminal Vd.
At d, the drain is grounded to the ground Vss via the resistor R1. At this time, the current driving capability of the output transistor Q2 is reduced to about twice the current of the resistor R1, and the current driving capability of the output transistor Q1 is designed to be sufficiently large. The common drain of the transistors Q1 and Q2 is connected to the load circuit 9 as an output terminal of the reference voltage generating circuit 120 and to the non-inverting input terminals of the error amplifiers 1 and 2.

According to this configuration, the output voltage is raised in a short time by using both the output transistors Q1 and Q2 until the output voltage reaches 2.7V, and when the output voltage reaches 2.7V, the output transistor Q1 is turned off and the output transistor Q1 is turned off. Only Q2 works to raise the output to 3.0V.

As described above, when the power is turned on, a transistor having a large driving capability is operated to secure a current capability.
By operating the circuit using an output transistor whose driving ability is suppressed to the same level as the ability to constantly reduce the output voltage, the output voltage is prevented from excessively fluctuating due to noise or the like.

FIG. 13 shows a configuration example of a voltage regulator that outputs a predetermined voltage (Japanese Patent No. 29538).
87 specification). In FIG. 13, the voltage regulator 1
Reference numeral 30 denotes error amplifiers 1 and 2, P-type transistors Q1 and N
It comprises a type transistor Q2, a resistor R1, a resistor R2, and a resistor R3.

The gate of the transistor Q1 is connected to the error amplifier 1
The source is connected to the power supply terminal Vdd, the drain is connected to the ground Vss via the resistors R1, R2, and R3 in series, and serves as the output terminal of the voltage regulator 130. The internal reference voltage Vref is input to the inverting input terminal of the error amplifier 1, and the divided potential at the connection point between the resistors R1 and R2 is input to the non-inverting input terminal. On the other hand, the gate of the N-type transistor Q2 is connected to the output of the error amplifier 2, the source is connected to the ground Vss, and the drain is connected to the output terminal.
The inverting input terminal of the error amplifier 2 has an internal reference voltage V
ref is input, and the non-inverting input terminal inputs the divided potential at the connection point between the resistors R2 and R3.

According to this configuration, the internal reference voltage Vref
And the output voltage Vout is as follows: Vout = Vref * (R1 / (R2 + R3) +1), and the output voltage Vout is constant.

In the steady state, a voltage lower by VA (approximately several tens mV) is fed back to the error amplifier 2 by the voltage drop of the resistor R2, so that the N-type transistor Q2 is in a cut-off state. Here, when the temperature of the output terminal becomes high with no load, the off-leakage current of the P-type transistor Q1 increases exponentially to increase the output voltage. At this time, if the voltage fed back to the error amplifier 2 rises by ΔVA, the output of the error amplifier 2 becomes high gain and turns on the N-type transistor Q2 to suppress the rise of the output voltage. This prevents an increase in output voltage due to off-leak current of P-type transistor Q1.

[0013]

In the conventional reference voltage generating circuit 110 shown in FIG. 11, the current flowing through the resistor R1 connected between the drain of the output transistor Q1 and the ground Vss is consumed as a steady leakage current. In general, a value of the order of several MΩ to several tens of MΩ is selected for the resistor R1 in a system such as a portable terminal device, because it affects the current. Further, the current driving capability of the output transistor Q1 is determined by improving the rising characteristics of the reference voltage generation circuit 110 and by the maximum value of the current supply capability required by the load circuit 9, so that a large driving capability can be obtained. And several tens of mA to several hundred m depending on the system.
The order of A is reached.

[0014] In this way, to suppress steady current consumption,
In order to satisfy the two requirements of maintaining a high current supply capability, a method of combining a resistor R1 having a high resistance value and an output transistor Q1 having a high driving capability has conventionally been adopted. On the other hand, a wiring capacitance is parasitic on the output voltage wiring of the reference voltage generating circuit 110, and a stabilizing capacitance C is often connected to the output terminal as a part of a load circuit for removing noise components due to its characteristics. .

Here, in the above system, there is a problem that the transient response is remarkably deteriorated due to the capacitance C connected to the output terminal due to the large difference between the current driving capability of the resistor R1 and the current driving capability of the output transistor Q1. Occurs.

That is, when sudden noise is superimposed on the power supply Vdd or positive noise is generated in the internal reference voltage Vref, the output voltage Vout becomes higher than a specified value. In addition, when the output current sharply decreases due to the operation of the load circuit 9, the output voltage Vout overshoots due to the operation delay of the control loop of the drain voltage Vq1d, the error amplifier 1, and the output transistor Q1. This state is shown by the dashed line in FIG. As shown in FIG.
The charge is charged to the capacitor C by the high driving capability of the output transistor Q1, and once such charge is charged, the path for discharging the charge only has the resistor R1 having a high resistance value. A phenomenon occurs in which the output voltage Vout is kept high for a long time due to the charged electric charge. Further, when such an external factor for increasing the output voltage is applied in a short cycle, there is a problem that the output voltage Vout constantly increases.

In order to deal with these problems, FIG. 12 (JP-A-5-114291) discloses two output transistors Q1 and Q2 having different current driving capabilities,
It is proposed that both transistors be started up to near ref, and that an output transistor Q2 having a low driving capability, which is about twice the resistance R1 of a high resistance value, be used constantly. However, in this configuration, noise is superimposed only on the internal reference voltage Vref, and the output current is small, and the output transistor Q2
Although it works effectively when operating in the range of driving capability described above, it cannot cope with a system in which the output current fluctuates greatly.

That is, as shown by the broken line in FIG. 14, when the output current fluctuates beyond the current driving capability of the output transistor Q2 having a low driving capability, the output voltage is allowed to fluctuate up to the set threshold width. As a result, the output transistor Q1 having a high driving capability is made conductive, so that an overshoot of the output voltage occurs when the load current stops. Therefore,
In the situation where the fluctuation amount reaches this range, the existing problem that the output voltage does not return for a long time while increasing cannot be avoided. In order to suppress this, after all, the current driving capability of the resistor R1 is increased to allow an increase in leakage current, or the current driving capability of the output transistor is increased to reduce the output voltage when the current is reduced. Therefore, it is inevitable to take measures such as setting the threshold value not to exceed the threshold value, and the effect on noise disappears.

In a reference voltage generating circuit and a voltage regulator having conventionally proposed configurations, when the output current becomes high in a minute state or in a no-load state, the output transistor increases its off-leakage current to increase the output current. There was a problem that the voltage increased. In FIG. 13 (a circuit proposed in Japanese Patent No. 2953887), when the output rises beyond a certain threshold value due to the generation of the off-leakage current, a reverse conductive channel provided in parallel with a resistor between the drain and ground of the output transistor. However, there is an inherent problem that the output voltage can be increased up to the threshold width due to the resistance.

Further, in the circuit of FIG. 13, as an additional effect, the transient response of the output voltage can be limited at the stage when the output voltage exceeds the threshold value. It is conceivable that a certain effect is exerted in the transient fluctuation accompanied by the above, but the effect largely depends on the setting of the threshold width.

Therefore, the present invention can be applied to a system that requires a large current supply capability without sacrificing a steady leakage current, and a voltage generation method and a voltage generation method having a high-speed transient response of an output voltage. It is an object to provide a generation circuit, a voltage regulator, and a portable terminal device using the same.

Another object of the present invention is to provide a voltage generation method, a voltage generation circuit, a voltage regulator, and a portable terminal device using the same, which can avoid an increase in the output voltage due to the influence of off-leakage current which is not affected by the setting of the threshold value. The purpose is to provide.

[0023]

According to the voltage generating method of the present invention, an output transistor and a resistor are connected in series between power supply terminals and output from the connection point to a load. In a voltage generation method in which a voltage or a voltage obtained by dividing the voltage and an internal reference voltage are error-amplified to control a gate voltage of the output transistor and generate a constant-voltage output voltage, a low input resistance A low input resistance constant voltage generating means for generating a constant voltage equal to the target value of the output voltage, and when there is a difference between the voltage of the low input resistance constant voltage generating means and the output voltage, the connection point And the output of the low input resistance constant voltage generating means is connected by a switch.

According to the voltage generation method of the first aspect, in the method of connecting an output transistor and a resistor in series between power supply terminals and generating an output voltage controlled at a constant voltage from the connection point to a load, a low input resistance A low input resistance constant voltage generating means for generating a constant voltage equal to the target value of the output voltage,
When there is a difference between the voltage of the low input resistance constant voltage generating means and the output voltage (or the divided voltage), the connection point and the low input resistance constant voltage generating means are connected by a switch. As a result, it is possible to realize a reference voltage generation circuit that has a fast rising characteristic, excellent driving capability, and excellent transient characteristics due to load fluctuation even when a large capacitance is connected.

Further, in a steady state, the leakage current is reduced by the high resistance, so that the current consumption is effectively exerted.

According to a second aspect of the present invention, there is provided a voltage generating circuit comprising:
An output transistor Q1 connected between the first power supply terminal Vdd and the output terminal, a first resistor R1 connected between the output terminal and the second power supply terminal Vss, an internal reference voltage Vref to an inverting input, and an output terminal voltage A first error amplifier having an input connected to the non-inverting input and an output connected to the gate of the output transistor, and a low input resistance constant voltage generating means for forming a constant potential point having a low input resistance and a constant voltage equal to the internal reference voltage And a switch means connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage.

According to the voltage generating circuit of the present invention, the low input resistance constant voltage generating means is provided, and when the output voltage rises, the output potential point is connected to the low input resistance constant voltage generating means. The startup characteristics are high speed and the driving capability is excellent,
In addition, even when a large capacitance is connected, it is possible to realize a reference voltage generating circuit having a good transient characteristic due to a load change or the like.

In a steady state, the leakage current is reduced by the high resistance, so that the current consumption can be effectively reduced.

Further, since it is not necessary to provide a threshold value for the output fluctuation, the design is facilitated, and the setting of the threshold value does not include a factor in which a transient characteristic is traded off.

According to a third aspect of the present invention, there is provided a voltage generating circuit comprising:
3. The voltage generating circuit according to claim 2, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch SW driven by an output of the comparator.
1 is constituted.

According to the voltage generating circuit of the third aspect, in addition to the effect achieved by the voltage generating circuit of the second aspect, since the switch means is constituted by the comparator 3 and the switch SW1,
Since a very small offset such as an error amplifier can be absorbed by the comparator to determine the operating point, a more stable control operation can be performed.

According to a fourth aspect of the present invention, there is provided a voltage generating circuit comprising:
4. The voltage generating circuit according to claim 3, wherein the switch driven by the output of the comparator is a transistor switch Q3.
It is characterized by being.

According to the voltage generating circuit of the fourth aspect, in addition to the effect achieved by the voltage generating circuit of the third aspect, the transistor switch Q3 is controlled to be turned on and off by the output of the comparator, and its on resistance has no problem in voltage drop. Low resistance,
By the action of the parasitic diode D3, even if an output abnormality occurs on any side of the transistor switch Q3, it is possible to converge even if an offset of the forward voltage is included, and it is advantageous for monolithic including this switch. is there.

According to a fifth aspect of the present invention, there is provided a voltage generation circuit comprising:
In the voltage generating circuit according to the second aspect, the switch means is a diode D1 provided so as to conduct from the output terminal toward the constant potential point.

According to the voltage generating circuit of the fifth aspect, in addition to the effect achieved by the voltage generating circuit of the second aspect, the diode D1 is provided so that the switch means conducts from the output terminal toward the constant potential point. Therefore, although an offset corresponding to the forward voltage of the diode remains, the switch means is composed of only the diode, so that the circuit configuration is simple, the number of parts can be reduced, and the required area when integrated into an IC is reduced. can do.

According to the voltage generating circuit of the present invention,
The voltage generating circuit according to claim 2, wherein the switch means is diodes D1 and D2 connected in anti-parallel.

According to the voltage generating circuit of the sixth aspect, in addition to the effect achieved by the voltage generating circuit of the second aspect, the switch means is provided with an anti-parallel diode between the output terminal and the constant potential point. Therefore, although the offset amount corresponding to the forward voltage of the diode remains, the switch means is composed only of the diode, so that the circuit configuration is simple, the number of parts can be reduced, and the required area when integrated into an IC is reduced. Can be. Further, even if an output abnormality occurs on any side of the switch means, it is possible to converge as quickly as possible.

According to a seventh aspect of the present invention, there is provided a voltage generation circuit comprising:
An output transistor Q1 connected between the first power supply terminal Vdd and the output terminal, a first resistor R1 connected between the output terminal and the second power supply terminal Vss, an internal reference voltage Vref to an inverting input, and an output terminal voltage A first error amplifier having an input connected to the non-inverting input and having an output connected to the gate of the output transistor, and a rechargeable battery or capacitor including a low input resistance and a constant potential point having a constant voltage equal to the internal reference voltage And a switch means connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. It is characterized by the following.

According to the voltage generating circuit of the seventh aspect, the same effect as that of the voltage generating circuit of the second aspect can be obtained.
By configuring the low input resistance constant voltage generating means with a chargeable battery or capacitor, excess charge can be absorbed. In particular, in the case of a rechargeable battery, the battery is charged by the charge absorbed by the battery, so that the excess charge that was originally wasted can be reused as battery energy, and energy saving can be achieved. .

According to the voltage generating circuit of the present invention,
8. The voltage generating circuit according to claim 7, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch SW driven by an output of the comparator.
1 is constituted.

According to a ninth aspect of the present invention, there is provided a voltage generation circuit comprising:
9. The voltage generating circuit according to claim 8, wherein the switch driven by the output of the comparator is a transistor switch Q3.
It is characterized by being.

According to a tenth aspect of the present invention, in the voltage generating circuit of the seventh aspect, the switching means is a diode D1 provided to conduct from the output terminal toward the constant potential point. It is characterized by the following.

The voltage generating circuit according to claim 11 of the present invention is characterized in that, in the voltage generating circuit according to claim 7, the switch means is diodes D1 and D2 connected in anti-parallel.

According to the voltage generating circuits of the eighth, ninth, tenth, and eleventh aspects, the same effects as those of the voltage generating circuits of the seventh aspect and the same effects as those of the third to sixth aspects are exhibited. be able to.

According to a twelfth aspect of the present invention, there is provided a voltage generation circuit comprising: a first power supply terminal connected between a first power supply terminal and an output terminal;
The conductivity type output transistor Q1, the first resistor R1 connected between the output terminal and the second power supply terminal Vss, the internal reference voltage Vref is input to the inverting input, the output terminal voltage is input to the non-inverting input, and the output is the first input. A first error amplifier 1 connected to the gate of the conductivity type output transistor, a second resistor R2 connected between the first power supply terminal Vdd and the constant potential point Vq2d,
A second conductivity type transistor Q2 connected between the constant potential point Vq2d and the second power supply terminal Vss, and an internal reference voltage Vref
Is input to the inverting input, the constant potential point voltage is input to the non-inverting input,
The second error amplifier 2 whose output is connected to the gate of the transistor of the second conductivity type, is connected between the output terminal and the constant potential point, and when a difference occurs between the output terminal voltage and the constant potential point voltage, Switch means to be turned on.

According to the voltage generating circuit of the twelfth aspect, the basic operation and effect are the same as those of the second aspect, and the low input resistance constant voltage generating means is replaced by a high resistance resistor, an N-type transistor, Since the circuit is composed of the second error amplifier, the circuit can be easily assembled in the same manner as the P-type output transistor, the high-resistance resistor, and the first error amplifier. Further, although it is related to the configuration of the switch means, all circuits can be configured by ordinary electronic circuit means, and it is easy to make it monolithic.

According to a thirteenth aspect of the present invention, in the voltage generating circuit of the twelfth aspect, the switch means includes a comparator 3 to which an output terminal voltage and a constant potential point voltage are inputted, And a switch SW1 driven by the output of the container.

According to a fourteenth aspect of the present invention, in the voltage generating circuit according to the thirteenth aspect, the switch driven by the output of the comparator is a transistor switch Q3.

A voltage generating circuit according to a fifteenth aspect of the present invention is the voltage generating circuit according to the twelfth aspect, wherein the switching means is a diode D1 provided so as to conduct from the output terminal toward the constant potential point. It is characterized by the following.

A voltage generating circuit according to a sixteenth aspect of the present invention is the voltage generating circuit according to the twelfth aspect, wherein the switching means is a diode connected in anti-parallel.

According to the voltage generating circuits of the thirteenth, fourteenth, fifteenth, and sixteenth aspects, the same effects as those of the third to sixth aspects can be obtained in addition to the effects of the voltage generating circuit of the twelfth aspect. be able to.

According to a seventeenth aspect of the present invention, there is provided a voltage generation circuit comprising: a first power supply terminal connected between a first power supply terminal and an output terminal;
The conductivity type output transistor Q1, the first resistor R1 connected between the output terminal and the second power supply terminal Vss, the internal reference voltage Vref is input to the inverting input, the output terminal voltage is input to the non-inverting input, and the output is the first input. A first error amplifier 1 connected to the gate of the conductivity type output transistor, a second resistor R2 connected between the first power supply terminal Vdd and the constant potential point Vq2d,
A second conductivity type transistor Q2 connected between the constant potential point Vq2d and the second power supply terminal Vss, and an internal reference voltage Vref
Is input to the inverting input via the diode D3, the constant potential point voltage is input to the non-inverting input, and the output is connected to the gate of the transistor of the second conductivity type. And a diode D1 connected between the output terminal and the constant potential point when a difference occurs between the output terminal voltage and the constant potential point voltage.

The voltage generating circuit according to claim 18 of the present invention comprises a first power supply terminal Vdd connected between the first power supply terminal Vdd and the output terminal.
The conductivity type output transistor Q1, the first resistor R1 connected between the output terminal and the second power supply terminal Vss, the internal reference voltage Vref is input to the inverting input, the output terminal voltage is input to the non-inverting input, and the output is the first input. A first error amplifier 1 connected to the gate of the conductivity type output transistor, a second resistor R2 connected between the first power supply terminal Vdd and the constant potential point Vq2d,
A second conductivity type transistor Q2 connected between the constant potential point Vq2d and the second power supply terminal Vss, and an internal reference voltage Vref
Is input to the inverting input via the diode D3, the constant potential point voltage is input to the non-inverting input, and the output is connected to the gate of the transistor of the second conductivity type. And diodes D1 and D2 connected in anti-parallel and connected so as to conduct when a difference occurs between the output terminal voltage and the constant potential point voltage.

According to the voltage generation circuit of the present invention, in order to cancel an error component due to the forward voltage Vf1 of the diode D1 as the switch means, the input of the reference voltage Vref from the internal reference voltage circuit is performed by the diode. The signal is supplied to the inverting input terminal of the second error amplifier 2 via D3. As a result, the voltage difference between the drain voltage of the output transistor Q1 and the drain voltage of the transistor Q2 is kept equal to the forward voltage Vf1 of the diode D1 as the switching means. Function restrictions can be eliminated.

In addition, the effect of the diode described in claim 5 or claim 6, that is, since the switch means is composed of only the diode, the circuit configuration is simple, the number of parts can be reduced, and the IC is realized. In this case, the required area can be reduced, or the switch means is composed of only diodes, so that the circuit configuration is simple, the number of parts can be reduced, and the required area in the case of an IC can be reduced. . Even if an output abnormality occurs on either side of the switch means, it is possible to converge as quickly as possible.

According to a nineteenth aspect of the present invention, there is provided a voltage generation circuit comprising: a first power supply terminal connected between a first power supply terminal and an output terminal;
The conductivity type output transistor Q1, the first resistor R1 connected between the output terminal and the second power supply terminal Vss, the internal reference voltage Vref is input to the inverting input, the output terminal voltage is input to the non-inverting input, and the output is the first input. A first error amplifier 1 connected to the gate of the conductivity type output transistor; a gate resistor R2 ', a second resistor R2, and a first power supply connected in series between the first power supply terminal Vdd and the constant potential point Vq2d. A fourth diode D4 that conducts in the direction from the terminal Vdd to the constant potential point Vq2d
And a gate resistor R2 'and a second resistor R2, which are connected in parallel to a series circuit. The gate is connected to the gate resistor R2' and the second resistor R2.
Transistor Q4 connected to the connection point
A second conductivity type transistor Q2 connected between the constant potential point Vq2d and the second power supply terminal Vss;
ef is input to the inverting input via the third diode D3, the constant potential point voltage is input to the non-inverting input, and the output is connected to the gate of the transistor of the second conductivity type. A first diode D1 connected between the output terminal terminal and the constant potential point voltage and connected to the constant potential point Vq2d when a difference occurs between the output terminal voltage and the constant potential point voltage; The second resistor R2 is connected between a connection point between the second resistor R2 and the fourth diode D4 and the output terminal.
And a second diode D2 provided so as to conduct from the connection point of the second and fourth diodes D4 to the output terminal.

According to the voltage generating circuit of the nineteenth aspect, the same effect as that of the voltage generating circuit of the eighteenth aspect can be obtained.
By connecting the diode D1 and the second diode D2 via the fourth diode D4, the potential difference of the second diode D2 in the steady state is made equal to the forward voltage Vf1, so that the forward voltage of the diode D2 is used. Function restrictions can be eliminated.

A first conductivity type transistor Q4 connected in parallel to a series circuit of a gate resistor R2 'and a second resistor R2.
Is connected to the connection point between the gate resistor R2 'and the second resistor R2, the first conductivity type transistor Q4 is turned on only at the moment when the output voltage Vout temporarily drops below the set voltage, so that the time delay occurs. Therefore, a drop in the output voltage Vout can be suppressed.

According to a twentieth aspect of the present invention, there is provided a voltage generation circuit comprising: a first power supply terminal connected between a first power supply terminal and an output terminal;
The conductivity type output transistor Q1, the first resistor R1 connected between the output terminal and the second power supply terminal Vss, the internal reference voltage Vref is input to the inverting input, the output terminal voltage is input to the non-inverting input, and the output is the first input. A first error amplifier 1 connected to the gate of the conductivity type output transistor, and a second resistor R connected in series between the first power supply terminal Vdd and the constant potential point Vq2d.
A fourth diode D4 conducting in the direction from the second power supply terminal Vdd to the constant potential point Vq2d, and a second resistor R2 connected in parallel, a gate connected to the first power supply terminal Vdd via the gate resistor R4, Further, a first conductivity type transistor Q4 whose gate is connected to a connection point of the second resistor R2 and the fourth diode D4 via a gate capacitor C4, and a second transistor Q4 connected between the constant potential point Vq2d and the second power supply terminal Vss. The conductivity type transistor Q2 and the internal reference voltage Vref are the third
A second error amplifier 2 having a constant potential point voltage input to the non-inverting input and a non-inverting input via the diode D3 and an output connected to the gate of the second conductivity type transistor, and an output terminal connected to the constant potential point Vq2d. A first diode D1 connected between the output terminal and the constant-potential point voltage so as to conduct from the output terminal to the constant-potential point Vq2d, and a second resistor R2. A second diode D2 connected between the connection point of the fourth diode D4 and the output terminal, and provided so as to conduct from the connection point of the second resistor R2 and the fourth diode D4 toward the output terminal; It is characterized by the following.

According to the voltage generating circuit of the twentieth aspect, the same effects as those of the voltage generating circuit of the eighteenth aspect can be obtained.
By connecting the diode D1 and the second diode D2 via the fourth diode D4, the potential difference of the second diode D2 in the steady state is made equal to the forward voltage Vf1, so that the forward voltage of the diode D2 is used. Function restrictions can be eliminated.

Then, the gate of the first conductivity type transistor Q4 connected in parallel with the second resistor R2 is connected to the gate resistor R4.
4. The first power supply terminal Vdd via the gate capacitor C4
And the output terminal, the first conductivity type transistor Q4 is more stably turned on only at the moment when the output voltage Vout temporarily drops below the set voltage without being affected by the fluctuation of the power supply voltage. The drop of the output voltage Vout can be suppressed without time delay.

According to a voltage regulator of the present invention, an output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a first resistor connected in series between the output terminal and the second power supply terminal Vss. R11 and the second resistor R12 and the internal reference voltage Vref are input to the inverting input, and the connection point voltage of the first and second resistors is input to the non-inverting input;
A first error amplifier having an output connected to the gate of the output transistor, a low input resistance constant voltage generating means for forming a constant potential point of a constant voltage equal to the output voltage target value with a low input resistance,
A switch connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage.

A voltage regulator according to a twenty-second aspect of the present invention is the voltage regulator according to the twenty-first aspect, wherein the switch means includes a comparator 3 to which an output terminal voltage and a constant potential point voltage are inputted, It is characterized by comprising a switch SW1 driven by an output.

A voltage regulator according to a twenty-third aspect of the present invention is the voltage regulator according to the twenty-second aspect, wherein the switch driven by the output of the comparator comprises:
It is a transistor switch Q3.

A voltage regulator according to a twenty-fourth aspect of the present invention is the voltage regulator according to the twenty-first aspect, wherein the switch means is a diode D1 provided so as to conduct from the output terminal toward the constant potential point. Features.

A voltage regulator according to a twenty-fifth aspect of the present invention is the voltage regulator according to the twenty-first aspect, wherein the switch means is diodes D1 and D2 connected in anti-parallel.

A voltage regulator according to a twenty-sixth aspect of the present invention provides an output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a first resistor connected in series between the output terminal and the second power supply terminal Vss. R11 and the second resistor R12 and the internal reference voltage Vref are input to the inverting input, and the connection point voltage of the first and second resistors is input to the non-inverting input;
A first error amplifier 1 having an output connected to the gate of the output transistor, and a rechargeable battery or capacitor;
A low input resistance constant voltage generating means for forming a constant potential point of a constant voltage equal to the internal reference voltage with a low input resistance, and connected between the output terminal and the constant potential point; Switch means that is turned on when a difference occurs.

According to a voltage regulator according to a twenty-seventh aspect of the present invention, in the voltage regulator according to the twenty-sixth aspect, the switch means includes: a comparator 3 to which an output terminal voltage and a constant potential point voltage are input; It is characterized by comprising a switch SW1 driven by an output.

A voltage regulator according to a twenty-eighth aspect of the present invention is the voltage regulator according to the twenty-seventh aspect, wherein the switch driven by the output of the comparator comprises:
It is a transistor switch Q3.

A voltage regulator according to a twenty-ninth aspect of the present invention is the voltage regulator according to the twenty-sixth aspect, wherein the switch means is a diode D1 provided so as to conduct from an output terminal toward a constant potential point. Features.

A voltage regulator according to claim 30 of the present invention is characterized in that, in the voltage regulator according to claim 26, the switch means is diodes D1 and D2 connected in anti-parallel.

A voltage regulator according to a thirty-first aspect of the present invention includes a first conductivity type output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a series connection between the output terminal and a second power supply terminal Vss. The first resistor and the second
A first error in which the resistor and the internal reference voltage Vref are input to the inverting input, the node voltage of the first resistor R11 and the second resistor R12 is input to the non-inverting input, and the output is connected to the gate of the first conductivity type output transistor Amplifier 1 and first power supply terminal Vdd
A third resistor R connected in series between the power supply terminal Vss
2, a fourth resistance R21 and a fifth resistance R22, a second conductivity type transistor Q2 connected between a connection point of the third resistance and the fourth resistance and the second power supply terminal Vss, and an internal reference voltage Vre.
f is input to the inverting input, the connection point voltage of the fourth resistor and the fifth resistor is input to the non-inverting input, and the output is connected to the gate of the transistor of the second conductivity type. Switch means connected between the connection point of the third resistance and the fourth resistance, which is turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. I do.

The voltage regulator according to claim 32 of the present invention is the voltage regulator according to claim 31, wherein the switch means comprises: a comparator 3 to which an output terminal voltage and a constant potential point voltage are input; It is characterized by comprising a switch SW1 driven by an output.

The voltage regulator according to claim 33 of the present invention is the voltage regulator according to claim 32, wherein the switch driven by the output of the comparator is:
It is a transistor switch Q3.

According to a voltage regulator according to a thirty-fourth aspect of the present invention, in the voltage regulator according to the thirty-first aspect, the switching means is a diode D1 provided so as to conduct from the output terminal toward the constant potential point. Features.

A voltage regulator according to a thirty-fifth aspect of the present invention is the voltage regulator according to the thirty-first aspect, wherein the switch means is diodes D1 and D2 connected in anti-parallel.

A voltage regulator according to a thirty-sixth aspect of the present invention includes a first conductivity type output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a series connection between the output terminal and a second power supply terminal Vss. The first resistor R11 and the second resistor R12, the internal reference voltage Vref is input to the inverting input, the node voltage of the first resistor and the second resistor is input to the non-inverting input, and the output is the gate of the first conductivity type output transistor. A first error amplifier 1 connected to the first power supply terminal Vdd
A third resistor R connected in series between the power supply terminal Vss
2, a fourth resistance R21 and a fifth resistance R22, a second conductivity type transistor Q2 connected between a connection point of the third resistance and the fourth resistance and the second power supply terminal Vss, and an internal reference voltage Vre.
f is connected to the inverting input through a diode, and the fourth resistor and the fifth
The connection point voltage of the resistor is input to the non-inverting input, and the output is
A second error amplifier 2 connected to the gate of the conductivity type transistor, connected between the output terminal and a connection point of the third resistor and the fourth resistor serving as a constant potential point, and having an output terminal voltage and a constant potential point voltage. And a diode D1 provided so as to conduct from the output terminal toward the constant potential point when a difference occurs between the two.

The voltage regulator according to claim 37 of the present invention is a first conductivity type output transistor Q1 connected between the first power supply terminal Vdd and the output terminal, and is connected in series between the output terminal and the second power supply terminal Vss. The first resistor R11 and the second resistor R12, the internal reference voltage Vref is input to the inverting input, the node voltage of the first resistor and the second resistor is input to the non-inverting input, and the output is the gate of the first conductivity type output transistor. A first error amplifier 1 connected to the first power supply terminal Vdd
A third resistor R connected in series between the power supply terminal Vss
2, a fourth resistance R21 and a fifth resistance R22, a second conductivity type transistor Q2 connected between a connection point of the third resistance and the fourth resistance and the second power supply terminal Vss, and an internal reference voltage Vre.
f is connected to the inverting input through a diode, and the fourth resistor and the fifth
The connection point voltage of the resistor is input to the non-inverting input, and the output is
A second error amplifier 2 connected to the gate of the conductivity type transistor, connected between the output terminal and a connection point of the third resistor and the fourth resistor serving as a constant potential point, and having an output terminal voltage and a constant potential point voltage. And diodes D1 and D2 connected in anti-parallel and provided so as to be conductive when a difference occurs between them.

A voltage regulator according to a thirty-eighth aspect of the present invention includes a first conductivity type output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a series connection between the output terminal and the second power supply terminal Vss. The first resistor R11 and the second resistor R12 and the internal reference voltage Vref are input to the inverting input, the voltage at the node between the first resistor R11 and the second resistor R12 is input to the non-inverting input, and the output is the first conductivity type output transistor. The first error amplifier 1 is connected to the gate of the first power supply terminal Vdd and the gate resistor R2 ', the third resistor R2 and the first power supply terminal Vdd connected in series between the first power supply terminal Vdd and the constant potential point Vq2d. A fourth diode D4, which conducts in the direction of the potential point Vq2d, is connected in parallel to a series circuit of a gate resistor R2 'and a third resistor R2, and the gate is connected to the gate resistor R2' and the third resistor R2. A first conductivity type transistor Q4 which is connected to the point, the constant potential point Vq2d and a second power supply terminal Vss
A second conductivity type transistor Q2 connected therebetween, a series fourth resistor R21 and a fifth resistor R22 connected in parallel to the second conductivity type transistor Q2, and an internal reference voltage V2.
ref is input to the inverting input via the third diode D3,
The voltage at the connection point between the resistor and the fifth resistor is input to the non-inverting input, and the output is connected between the output terminal and the constant potential point Vq2d, the second error amplifier 2 having an output connected to the gate of the second conductivity type transistor. A first diode D1 provided to conduct from the output terminal to the constant potential point Vq2d when a difference occurs between the output terminal voltage and the constant potential point voltage;
A second diode D2 connected between a connection point between the resistor R2 and the fourth diode D4 and the output terminal, and provided so as to conduct from the connection point between the third resistor R2 and the fourth diode D4 toward the output terminal; , Is characterized by having.

A voltage regulator according to a thirty-ninth aspect of the present invention includes a first conductivity type output transistor Q1 connected between a first power supply terminal Vdd and an output terminal, and a series connection between the output terminal and the second power supply terminal Vss. The first resistor R11 and the second resistor R12 and the internal reference voltage Vref are input to the inverting input, the voltage at the node between the first resistor R11 and the second resistor R12 is input to the non-inverting input, and the output is the first conductivity type output transistor. The first error amplifier 1 connected to the gate of the first power supply terminal, the third resistor R2 connected in series between the first power supply terminal Vdd and the constant potential point Vq2d, and the direction from the first power supply terminal Vdd to the constant potential point Vq2d. A fourth diode D4 that conducts;
The gate is connected to the first power supply terminal Vdd via the gate resistor R4, and the gate is connected to the connection point between the third resistor R2 and the fourth diode D4 via the gate capacitor C4. A first conductivity type transistor Q4, a second conductivity type transistor Q2 connected between the constant potential point Vq2d and the second power supply terminal Vss, and a fourth series resistor connected in parallel to the second conductivity type transistor Q2. R21 and the fifth resistor R22, and the internal reference voltage Vref
Are input to the inverting input via the third diode D3, the connection point voltage of the fourth resistor and the fifth resistor is input to the non-inverting input, and the output of the second error amplifier 2 is connected to the gate of the transistor of the second conductivity type. , Connected between the output terminal and the constant potential point Vq2d, and provided so as to conduct from the output terminal to the constant potential point Vq2d when a difference occurs between the output terminal voltage and the constant potential point voltage. One diode D1 and a third resistor R2
A second diode D2 connected between the connection point of the fourth diode D4 and the output terminal, and provided so as to conduct from the connection point of the third resistor R2 and the fourth diode D4 toward the output terminal. It is characterized by having.

According to the voltage regulators of claims 21 to 39, the drain potential of the output transistor is steadily set to a value corresponding to the voltage dividing ratio by the two high-resistance resistors by comparison with the internal reference voltage Vref by the error amplifier. And the output voltage is determined. The operation and effect of the transient phenomenon are the same as those of the voltage generating circuit according to claims 2 to 20. From this, the voltage regulators of claims 21 to 39 can achieve the same effects as the reference voltage generation circuits of claims 2 to 20.

A portable terminal device according to claim 40 of the present invention is characterized by including the voltage generating circuit according to claims 2 to 20, or the voltage regulator according to claims 21 to 39.

The portable terminal device according to claim 40 is configured to include any one of the voltage generating circuits according to claims 2 to 20 or any one of the voltage regulators according to claims 21 to 39 as an internal power supply device. In addition, it is possible to secure a power supply that has a fast rise characteristic, excellent driving capability, good transient characteristics due to load fluctuations, a stable voltage, and low power consumption.

[0084]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a voltage generating circuit according to a first embodiment of the present invention as a reference voltage generating circuit. 1, reference voltage generating circuit 10 receives internal reference voltage Vref from internal reference voltage circuit 8 as a reference voltage generating source as a voltage command value, and includes load circuit 9 including capacitor C.
Outputs the output voltage Vout. Internal reference voltage circuit 8
Has a small current capacity, but outputs an accurate voltage as a reference voltage.For example, an N-channel depletion type MOS transistor is connected to a power supply side, and an N-channel enhancement type MOS transistor is connected to a ground side. Can be constituted by a transistor circuit in which the gate is short-circuited to the connection point. In addition, a power supply and a diode can be used. Load circuit 9
Requires a constant voltage and consumes power at an arbitrary time. For example, a semiconductor memory is assumed.

The reference voltage generating circuit 10 includes the error amplifier 1,
It comprises a low input resistance constant voltage generating means 4, a comparator 3, a P-type output transistor Q1, a resistor R1, and a switch SW1.

The output transistor Q1 is used to improve the rising characteristics of the reference voltage
The current driving capability is set large to compensate for the current supply capability required by the resistor R1. The resistor R1 is, for example, several MΩ to reduce the steady leakage current and the overall power consumption. A high resistance value on the order of tens of MΩ is selected.

The output transistor Q1 has a gate connected to the output terminal of the error amplifier 1, a source connected to the power supply terminal Vdd, a drain grounded to the ground Vss via the resistor R1, and a non-connected terminal of the error amplifier 1. Connected to inverting input terminal. The output transistor Q1
The load circuit 9 is connected as an output terminal of the reference voltage generation circuit 10 to the drain of the reference voltage generation circuit 10. The internal reference voltage Vr is applied to the inverting input terminal of the error amplifier circuit 1 by the internal reference voltage circuit 8.
ef is input.

The low input resistance constant voltage generating means 4 generates the same voltage Vref as the internal reference voltage Vref of the internal reference voltage circuit 8.
And the input resistance seen from the output side is set to a low value, and its output terminal forms a constant potential point.

The low input resistance constant voltage generating means 4 can be constituted by a rechargeable battery or capacitor charged to a predetermined voltage Vref. In this case, while having a charge supply capacity corresponding to the capacity, the voltage Vref is output, and when a voltage higher than the voltage Vref is supplied, the voltage is changed to a predetermined voltage Vref.
Operate to converge to

The comparator 3 is composed of, for example, an operational amplifier, and outputs the output voltage V of the low input resistance constant voltage generating means 4.
ref and the drain voltage Vq1d of the output transistor Q1
Are received at two input terminals, and both input voltages Vref, Vq1
Compare d. Then, both input voltages Vref, Vq1d
When a difference occurs, a comparison operation output is generated, and a command signal is output to the switch SW1. The operation of the comparator 3 is unidirectional, that is, the drain potential Vq of the output transistor Q1.
1d is the output voltage Vref of the low input resistance constant voltage generating means 4
It may only be activated when it is higher, in which case the objective can be largely achieved.

The output of the low input resistance constant voltage generating means 4 is connected to the drain of the transistor Q1 via the switch SW1. Drain potential Vq of output transistor Q1
1d, and the output voltage Vre of the low input resistance constant voltage generating means 4
f is input to the comparator 3, and the switch SW1 is turned on if there is a difference between the two potentials, and is turned off if there is no potential difference.

When an operational amplifier is composed of a CMOS monolithic IC, the absolute variation of the offset voltage can be reduced to a low value (for example, ± 1 by designing the operational amplifier while paying attention to the characteristics of the internal differential amplification transistor and the like.
(Less than 0 mV) is easy. If the output voltage of the low input resistance constant voltage generating means (a rechargeable battery or the like) 4 can be selected with high accuracy as the reference voltage Vref, the adjusting means in the reference voltage generating circuit 10 of the present invention will require the comparator 3 to have a slight offset adjusting circuit. Is enough. That is, since the error including the error of the error amplifier 1 and the error of the low input resistance and low voltage generating means 2 can be regarded as an error of the comparator 3, it is possible to perform a highly accurate adjustment only by correcting the offset voltage.

In such a configuration, normally, the drain potential Vq1d of the transistor Q1 is raised and lowered by comparing the gate potential with the internal reference voltage Vref by the error amplifier 1 to adjust the on-resistance of the output transistor Q1. The constant voltage is set equal to the internal reference voltage Vref.

When the output voltage Vout, that is, the drain potential Vq1d drops, the current driving capability of the output transistor Q1 is set to be large, and the ON resistance of the output transistor Q1 is reduced by the action of the error amplifier 1, The drain potential Vq1d recovers quickly.

Conversely, a sudden superposition of noise on the power supply Vdd, a generation of positive noise on the internal reference voltage Vref, or a drain voltage Vdq1− when the output current is rapidly reduced by the operation of the load circuit 9 The output voltage Vout becomes higher than a specified value due to an overshoot due to an operation delay of a control loop of the error amplifier 1-output transistor Q1 and an off-leak current of the output transistor Q1 which is concerned at no load or high temperature. In the case, the resistance R
Since 1 has a high resistance, rapid discharge of electric charges via the resistor R1 cannot be expected.

However, according to the present invention, the increase in the output voltage Vout is detected by the comparator 3 and the switch SW1 is turned on, so that the electric charge accumulated in the load capacitance C is reduced by the low input resistance constant voltage generating means. 4, the output voltage Vout is quickly reduced to a predetermined value Vref.
To converge.

The operating state during this time is shown in the characteristic diagram of FIG. FIG. 2 shows time on the horizontal axis and output voltage (left scale) and current (right scale) on the vertical axis, and the solid line in the figure is a characteristic diagram according to the circuit of the present invention. It is to be noted that a dashed line and a broken line in the figure are characteristic diagrams of a conventional circuit shown for comparison.

Referring to the characteristic diagram of FIG. 2, at first, since no load current is taken, the output voltage Vout is equal to the reference voltage Vout.
It is at a value (3V) equal to ref. When a large load current (about 30 mA) is taken, the output voltage tends to drop at that moment, but the output voltage Vout is kept constant by the control loop of the drain voltage Vq1d, the error amplifier 1 and the output transistor Q1. Note that the output voltage Vout remains at a slightly lower value while the load current is flowing due to a voltage drop due to wiring resistance or the like.

When the load current disappears, the drain voltage Vq1d starts to rise. This is detected and the drain voltage Vq1d-the error amplifier 1-the output transistor Q1
The output voltage Vout to the specified voltage Vre
However, the output voltage Vout overshoots (about 3.1 V) due to the delay of the control loop. The overshoot of the output voltage Vout is the same in the reference voltage generating circuit of the present invention and in the conventional circuit (FIG. 11).

However, in the present invention, the output voltage Vo
ut, that is, the voltage rise of the drain voltage Vq1d,
Is detected, and the switch 1 is closed. As a result, the charge accumulated in the load capacitance C is absorbed by the low input resistance constant voltage generation means 4 through the switch SW1, and the output voltage Vout quickly returns to the specified voltage Vref as shown in FIG. When this is compared with the characteristics of the conventional circuits (FIGS. 11 and 12), it can be seen that the improvement effect is large. As a matter of course, the output voltage Vout is equal to the specified voltage Vre.
When returning to f, the detection output of the comparator 3 is lost.
The switch SW1 is opened.

As described above, according to the reference voltage generating circuit of this embodiment, the low input resistance constant voltage generating means 4 is provided, and when the output voltage Vout rises, the output potential point is set to the low input resistance constant voltage generating means. , A reference voltage generating circuit having a high rise characteristic, excellent driving capability, and excellent transient characteristics due to load fluctuation even when a large capacitance is connected can be realized.

In addition, since the leakage current is reduced by the high resistance in the steady state, the current consumption can be effectively reduced.

Further, since it is not necessary to provide a threshold value for the output fluctuation, the design becomes easy, and there is no factor in which the transient characteristics are traded off by setting the threshold value.

Further, by configuring the low input resistance constant voltage generating means 4 with a rechargeable battery or capacitor,
Excess charge can be absorbed. In particular, in the case of a rechargeable battery, the battery is charged by the charge absorbed by the battery, so that the excess charge that was originally wasted can be reused as battery energy, and energy saving can be achieved. . Further, when the output power drops, the power can be temporarily supplied from the battery or the capacitor of the low input resistance constant voltage generating means 4, so that the supplied power is small, but the auxiliary action of accelerating the rise of the output voltage somewhat is provided. Can be fulfilled.

FIG. 3 is a diagram showing a reference voltage generating circuit according to a second embodiment of the present invention. In FIG. 3, the first
1 is different from FIG. 1 of the embodiment in that the low input resistance constant voltage generating means 4 of FIG.
Is constituted by a high-resistance resistor R2, an N-type transistor Q2, and a second error amplifier 2. Other configurations are the same as those of the embodiment of FIG. 1, and corresponding components are denoted by the same reference numerals.

A high-resistance resistor R2 and an N-type transistor Q
2 are connected in series such that the resistor R2 is on the power supply terminal Vdd side and the N-type transistor Q2 is on the ground Vss side. The error amplifier 2 is connected to the gate of the transistor Q2.
The output terminal of the error amplifier 2 is connected to the power supply terminal via the resistor R2, and the non-inverting input terminal of the error amplifier 2. The internal reference voltage Vref is input to the inverting input terminal of the error amplifier 2 by the internal reference voltage circuit.

As described above, the output transistor Q1 and the resistor R1 and the resistor R2 and the transistor Q2 are configured to have opposite polarities, and the connection point potential Vq1d between the output transistor Q1 and the resistor R1 is equal to the reference voltage Vref. It is controlled to be equal, and the connection point potential Vq2d between the resistor R2 and the transistor Q2 is also the same as the reference voltage Vref.
Is controlled to be equal to The drain of the output transistor Q1 and the drain of the transistor Q2 are connected via a switch SW1, and each drain potential V
q1d and Vq2d are input to the comparator 3, and the switch SW1 is turned on if there is a difference between the two drain potentials, and is turned off if there is no potential difference.

In such a configuration, the drain potentials Vq1d and Vq2d of the transistors Q1 and Q2 are constantly raised and lowered by comparing their internal potentials Vref with the internal reference voltage Vref by the error amplifiers 1 and 2, and the on-resistance of each transistor is increased. Is adjusted to a constant voltage equal to the internal reference voltage Vref.

In this embodiment, both transistors Q
FIG. 4 shows the response characteristics of the drain potentials Vq1d and Vq2d of the respective transistors to the output of the transient error amplifier due to a load change or the like of the drain potentials Vq1d and Vq2d of the transistors Q1 and Q2. Drain potential Vq of transistor Q1
As shown by the solid line in the figure, 1d shows a very fast rising characteristic when the response in the positive direction or power-on, that is, when the voltage is lower than the target value, due to the large driving ability of the output transistor Q1. Is delayed through the resistor R1 having a high resistance value.
Further, at the drain potential Vq2d of the transistor Q2,
Positive response or high resistance R
2, the rise is slow, but the response in the negative direction, that is, the response from a high voltage to a low voltage, is fast.

In the reference voltage generating circuit of FIG. 3, as in FIG. 1, the comparator 3 and the switch SW1 are used to short-circuit only at the moment when a difference occurs between the two drain potentials. In a transient state in which high-speed convergence of the output voltage is required, it is possible to compensate for a slow response portion, which was impossible in the conventional circuit, while suppressing the current by the high resistances R1 and R2. Therefore, in a system in which a large load capacity is connected, excess charge transiently charged due to load fluctuation can be charged and discharged at high speed, and high-speed convergence of output voltage can be obtained.

Also in this embodiment, when the off-leak current of the output transistor Q1 increases when the output terminal is in a no-load state or at a high temperature, and the drain potential increases, the increase in the off-leak current is determined by the switch SW1. , The output voltage can be kept constant.

Further, since the low input resistance constant voltage generating means 4 is constituted by the high resistance R2, the N type transistor Q2 and the second error amplifier 2, the high resistance R1 and the P type transistor Q1 are used. , And the first error amplifier 1, and the circuit configuration is easy.

FIG. 5 is a diagram showing a reference voltage generating circuit according to a third embodiment of the present invention. In FIG. 5, the second
FIG. 3 of the embodiment differs from FIG. 3 in that the switch SW1 in FIG. 3 is replaced by a P-type transistor Q3. D3 is a parasitic diode. Other configurations are the same as those in the second embodiment in FIG. 3, and corresponding components are denoted by the same reference numerals.

In FIG. 5, in a transient state involving output fluctuation, the drain potential Vq1d of the output transistor Q1 is shown.
Turns on the transistor Q3 strongly in a state where the voltage is rising with respect to the drain potential Vq2d of the transistor Q2,
The charge stored in the load capacitance C is discharged at high speed, and the output voltage Vou
t may converge to the regular output value Vref. Further, in this configuration, since the parasitic diode D3 of the transistor Q3 is provided, assuming that the ON voltage of the parasitic diode D3 is Vf, when the drain potential Vq2d of the transistor Q2 rises above Vq1d of the output transistor Q1, that is, Vq
If 2d> (Vq1d + Vf), the action of the parasitic diode D3 causes the drain potential V
q2d falls without a time delay. Therefore, even if an output abnormality occurs on any side of the transistor Q3, it is possible to converge.

The reference voltage generating circuit according to the third embodiment shown in FIG. 5 has the same effects as the second embodiment shown in FIG. 3, and further has a high resistance value as low input resistance constant voltage generating means. It comprises a resistor R2, an N-type transistor Q2, a second error amplifier 2, and a differential amplifier as a comparator 3,
By using the P-type transistor Q3 as the switching means, all circuits can be configured with ordinary electronic circuit means, and it is easy to make it monolithic.

FIG. 6 is a diagram showing a reference voltage generating circuit according to a fourth embodiment of the present invention. In FIG. 6, the second
FIG. 3 of the embodiment or FIG. 5 of the third embodiment is different from the switch SW1 of FIG. 3 or the P-type transistor Q3 of FIG. 5 in that antiparallel diodes D1 and D2 are used. Other configurations are the same as those in the second embodiment in FIG. 3, and corresponding components are denoted by the same reference numerals.

In FIG. 6, antiparallel diodes D1, D
2 uses a diode having a characteristic of rising at a forward voltage Vf1 as low as possible. Actually, a voltage having a forward voltage of about 0.2 V can be used. Therefore, it is effective to apply an output voltage to a reference voltage generating circuit in which the magnitude of the forward voltage does not matter.

In FIG. 6, in a transient state involving output fluctuation, the drain potential Vq1d of output transistor Q1 is shown.
With respect to the drain potential Vq2d of the transistor Q2,
In a state where the forward voltage Vf1 of the diode D1 has increased by the amount equal to or more than the forward voltage, the diode D1 is turned on to discharge the charge stored in the load capacitance C at a high speed, and to operate so that the output voltage Vout converges to the normal output value Vref. However, in this case,
An offset corresponding to the forward voltage of the diode D1 remains. The voltage of the remaining offset is the resistance R
1 will be discharged.

Further, in this configuration, since the diode D2 is provided, when the ON voltage is Vf1, the drain potential Vq2d of the transistor Q2 rises above the Vq1d of the output transistor Q1, that is, Vq
If 2d> (Vq1d + Vf1), the diode D
2, the drain potential Vq of the transistor Q2
2d descends without time delay. Therefore, even if an output abnormality occurs on either side of the diodes D1 and D2 connected in anti-parallel, it is possible to converge.

As a modification of the reference voltage generating circuit according to the fourth embodiment shown in FIG. 6, the diode D2 can be omitted and only the diode D1 can be used as a switching element. Also in this case, when the drain voltage Vq1d of the output transistor Q1, that is, the output voltage Vout becomes high, it has a basic function of rapidly lowering the voltage, and the object of the present invention is substantially achieved. Can be.

In the reference voltage generating circuit according to the fourth embodiment shown in FIG. 6, the same effects as those of the second embodiment shown in FIG. 3 can be obtained, and the switch means is constituted only by diodes D1, D2 or D1. Therefore, the circuit configuration is simple, the number of components can be reduced, and the required area when the IC is formed can be reduced.

FIG. 7 is a diagram showing a reference voltage generating circuit 70 according to a fifth embodiment of the present invention. In this FIG.
The input of the reference voltage Vref from the internal reference voltage circuit 8 is
The diode D3 and the resistor R3 are grounded, and the potential at the divided point is supplied to the inverting input terminal of the second error amplifier 2. Other configurations are the same as those in the fourth embodiment of FIG. 6, and corresponding components are denoted by the same reference numerals. Note that the resistor R3 can be included in the error amplifier 2.

In FIG. 7, the input of the reference voltage Vref from the internal reference voltage circuit 8 is supplied to the inverting input terminal of the second error amplifier 2 via the diode D3. This is for canceling an error component due to the forward voltage Vf1 of the diode D1 in the fourth embodiment of FIG. Generally, it is easy to form an element having a relatively paired property in a CMOS monolithic IC, and in the circuit of the present embodiment, it is assumed that the characteristics of the diode D3 and the diode D1 are the same, ,
The forward voltage of D3 is set to be substantially equal to Vf1.

As a result, the voltage supplied to the inverting input terminal of the second error amplifier 2 is a voltage obtained by subtracting the forward voltage Vf1 of the diode D3 from the reference voltage Vref (= Vref).
−Vf1). Therefore, the drain voltage Vq2d of the transistor Q2 is controlled to Vref-Vf1.

As a result, the drain voltage Vq1d of the output transistor Q1 and the drain voltage Vq
2d is equal to the forward voltage Vf1 of the diode D1.
Therefore, the function limitation due to the forward voltage of the diode D1 can be eliminated.

Also in this embodiment, the diode D2 connected in anti-parallel with the diode D1 can be eliminated, and only the diode D1 can be used as a switch element. Also in this case, when the drain voltage Vq1d of the output transistor Q1, that is, the output voltage Vout becomes high, it has a basic function of rapidly lowering the voltage, and the object of the present invention is substantially achieved. Can be.

The reference voltage generating circuit according to the fifth embodiment shown in FIG. 7 has the same effects as the fourth embodiment shown in FIG. By decreasing the forward voltage of the diode D1,
The influence of the forward voltage of the diode as the switching means can be eliminated, and the overvoltage absorption of the output voltage Vout can be performed with higher accuracy.

The processing for the offset voltage of the error amplifier constituted by the operational amplifier has been described in the first embodiment of FIG. The concept is the same in each of the second and subsequent embodiments. However, when it is not desired to use a diode as the switching means or to provide another adjusting means, the feedback voltage to the error amplifier 2 may be set low in advance by the maximum variation of the offset voltage. Specifically, for example, the feedback voltage to the error amplifier 2 can be adjusted by means such as resistance voltage division. As a result, the drain voltage Vq2d of the transistor Q2 is constantly output slightly higher than the drain voltage Vq1d of the output transistor Q1, so that the object of the present invention can be sufficiently achieved.

As described above, the reference voltage generating circuit has been described in detail with reference to some embodiments. However, the reference voltage generating circuit according to the present invention is not limited to these embodiments, and may be implemented in various other circuits. Can be. That is, as a low input resistance constant voltage generating means, a rechargeable battery or a capacitor, a high resistance R2, an N type transistor Q2, a second error amplifier 2, and a high resistance Resistance R2, N-type transistor Q
2, the second error amplifier 2
Is supplied via a diode. The switch means can be selected from a switch and a comparator, a transistor switch and a comparator, a unidirectional diode, and an anti-parallel diode. Therefore, by selecting and combining these configurations, reference voltage generating circuits having various circuit configurations can be formed.

FIG. 8 is a diagram showing a reference voltage generating circuit 80 according to a sixth embodiment of the present invention. In FIG. 8,
As in the fifth embodiment of FIG. 7, the input of the reference voltage Vref from the internal reference voltage circuit 8 is grounded via the third diode D3 and the resistor R3, and the potential at the voltage dividing point is applied to the second error amplifier 2. Is supplied to the inverting input terminal. In addition to this, in FIG. 8, instead of simply connecting the first diode D1 and the second diode D2 in anti-parallel, a fourth diode in which two diodes conducting in the direction from the power supply terminal Vdd to the ground Vss are connected in series. A diode D4 is provided.

Further, the gate resistance R2 'is added to the second resistance R2.
Are connected in series, a P-type transistor Q4 is connected in parallel with the second resistor R2 and the gate resistor R2 ', and the gate is connected to the series connection point of the second resistor R2 and the gate resistor R2'. . Note that the resistance value of the gate resistor R2 'is set to be considerably smaller than the resistance value of the second resistor R2, and the second resistor R2 may be provided with a tap terminal. Except for these components, the configuration is the same as that of the fifth embodiment of FIG. 7, and the corresponding components are denoted by the same reference numerals.

In FIG. 8, the reference voltage Vre from the internal reference voltage circuit 8 is the same as in the fifth embodiment shown in FIG.
The input of f is supplied to the inverting input terminal of the second error amplifier 2 via the third diode D3. 2nd error amplifier 2
Of the reference voltage Vref
Minus the forward voltage Vf1 of the third diode D3 (= Vref−Vf1), and the drain voltage Vq2d of the transistor Q2 is controlled to Vref−Vf1. As a result, the drain voltage Vq1d of the output transistor Q1 and the drain voltage Vq of the transistor Q2
q2d is maintained equal to the forward voltage Vf1 of the first diode D1.
It is possible to eliminate the functional limitation by the forward voltage of 1.

Further, by providing a fourth diode D4 (two diodes in series), the fourth diode D4 is provided.
4 and the second resistor R2 are connected to the transistor Q
2 becomes a voltage (= Vref + Vf1) higher than the drain voltage Vq2d (= Vref-Vf1) by two diodes of forward voltage 2Vf1. As a result, the voltage between both ends of the second diode D2 is kept equal to the forward voltage Vf1, so that the function limitation of the diode D2 due to the forward voltage can be eliminated.

On the other hand, the second resistor R2 and the gate resistor R2 '
Are set in such a manner that the gate voltage of the P-type transistor Q4 connected in parallel to the power supply voltage in a normal state is very close to the power supply voltage. Therefore, in the normal state, P
The transistor Q4 is in a cut-off state, and only the high-resistance second resistor R2 is effective on the path to the N-type transistor Q2.

When a load current flows from this state, the voltage drop at the gate resistor R2 'exceeds the threshold voltage of the P-type transistor Q4 only at the moment when the output voltage Vout temporarily drops below the set voltage. The P-type transistor Q4 is turned on and works to suppress a drop in the output voltage. According to the circuit of this embodiment, it is possible to configure a reference voltage generation circuit that does not cause a delay in the control loop and does not cause a drop or an excessive rise in the output voltage.

FIG. 9 is a diagram showing a reference voltage generating circuit 90 according to a seventh embodiment of the present invention. In FIG. 9,
The difference from the sixth embodiment of FIG. 8 is that the gate of the P-type transistor Q4 connected in parallel with the second resistor R2 having a high resistance value is connected to the first power supply terminal Vdd via the gate resistor R4. It is connected to a connection point between the second resistor R2 and the fourth diode D4 via the gate capacitor C4. That is,
The gate circuit of the P-type transistor Q4 has a gate resistance R4
And the gate capacitor C4 constitutes a high-pass filter. Other items are the same as those of the sixth embodiment shown in FIG. 8, and corresponding components are denoted by the same reference numerals.

In FIG. 9, since the gate circuit of the P-type transistor Q4 forms a high-pass filter, when the output voltage Vout drops, a voltage is applied to the gate resistor R4 by the amount of the drop, and The transistor Q4 is turned on. In the circuit of FIG. 8, since the gate voltage of the P-type transistor Q4 is input at a fixed voltage dividing ratio, it is affected by the fluctuation of the power supply voltage.
In the embodiment, a stable operation is performed without such a problem.

FIG. 10 is a diagram showing a voltage regulator 100 according to an eighth embodiment of the present invention. This figure 1
At 0, a resistor connected in series with the output transistor Q1 is a series connection of the resistors R11 and R12, and a feedback point is fed back to the non-inverting input terminal of the first error amplifier 1 from a connection point between the two resistors. I have. Further, a resistor R21 and a resistor R22 are connected in series in parallel with the N-type transistor Q2, and the connection point of the two resistors is fed back to the non-inverting input terminal of the second error amplifier 2.
Here, a resistor R2, an N-type transistor Q2, a resistor R2
1, the resistor R22 and the second error amplifier 2 constitute low input resistance constant voltage generating means, and the transistor Q3 and the comparator 3 constitute switching means. The other points are the same as those of the third embodiment of FIG. 5, and the corresponding components are denoted by the same reference numerals.

As described above, in the voltage regulator 100 according to the eighth embodiment of FIG. 10, the drain potential Vq1 of the transistor Q1 is connected to the non-inverting input terminal of the error amplifier 1.
d is divided by a high-resistance resistor R11 and a high-resistance resistor R12 and fed back, and a high-resistance resistor R21 and a high-resistance resistor R22 connected between the drain of the transistor Q2 and the ground to the non-inverting input terminal of the error amplifier 2 as well. , The drain potential Vq2d of the transistor Q2 divided equally to the resistors R11 and R12 is fed back.

In such a configuration, the drain potentials Vq1d and Vq2d of the transistors Q1 and Q2 are constantly compared with the internal reference voltage Vref by the error amplifiers 1 and 2 to obtain the voltage dividing ratios of the resistors R11 and R12 and R21 and R22. It is controlled to a corresponding value. That is, in the present circuit, a voltage regulator whose output voltage is determined by Vq1d = Vref * (R11 + R12) / R12 Vq2d = Vref * (R21 + R22) / R22 Vout = Vq1d = Vq2d is formed.

The effect of the present voltage regulator on transient phenomena is the same as that of the third embodiment shown in FIG.

The circuit configuration of the voltage regulator shown in FIG. 10 is merely an example, and the present invention is not limited to this, and various implementation circuits can be formed. That is, as in the case of the reference voltage generating circuit, the low input resistance constant voltage generating means is constituted by a rechargeable battery or a capacitor, the high resistance resistors R2, R21, R22, the N type transistor Q2, the second And the error amplifier 2 having a high resistance value, the resistors R2, R21, and R22 having a high resistance value, the N-type transistor Q2, and the second error amplifier 2;
Supply of the input of the error amplifier 2 through a diode. The switch means can be selected from a switch and a comparator, a transistor switch and a comparator, a unidirectional diode, and an anti-parallel diode. Therefore, by selecting and combining these configurations, voltage regulators having various circuit configurations can be configured.

Further, in the reference voltage generating circuits 80 and 90 shown in FIGS. 8 and 9 as the sixth and seventh embodiments, circuits for suppressing the drop of the output voltage Vout are similarly used. Can be configured.

The reference voltage generation circuit and the voltage regulator described in each of the above embodiments can be used in mobile phones,
It is used as a power supply device by being built in a portable terminal device such as a PHS, a notebook computer, a PDA, a digital camera, or connected from the outside. As a result, the portable terminal device can secure a power supply that has a fast start-up characteristic, excellent driving capability, good transient characteristics due to load fluctuation, a stable voltage generation, and low power consumption.

[0146]

According to the voltage generating method of the first aspect, the output transistor and the resistor are connected in series between the power supply terminals, and a constant voltage controlled output voltage is generated from the connection point to the load. A low input resistance constant voltage generating means for generating a constant voltage equal to the target value of the output voltage by an input resistance is provided, and a difference between the voltage of the low input resistance constant voltage generating means and the output voltage (or a divided voltage) is provided. Occurs, the connection point and the low input resistance constant voltage generating means are connected by a switch. As a result, it is possible to realize a reference voltage generation circuit that has a fast rising characteristic, excellent driving capability, and excellent transient characteristics due to load fluctuation even when a large capacitance is connected.

In addition, since the leakage current is reduced by the high resistance in the steady state, the current consumption can be effectively reduced.

According to the voltage generating circuit of the present invention, the low input resistance constant voltage generating means is provided, and when the output voltage rises, the output potential point is connected to the low input resistance constant voltage generating means, so that the rising is achieved. Characteristics are high speed and excellent driving ability,
In addition, even when a large capacitance is connected, it is possible to realize a reference voltage generating circuit having a good transient characteristic due to a load change or the like.

In the steady state, the leakage current is reduced by the high resistance, so that the current consumption is effectively reduced.

Further, since it is not necessary to provide a threshold value for the output fluctuation, the design becomes easy, and there is no factor in which the transient characteristic is traded off by setting the threshold value.

According to the voltage generating circuit of the third aspect, in addition to the effect of the voltage generating circuit of the second aspect, since the switch means is constituted by the comparator and the switch, a very small offset such as an error amplifier is provided. Can be determined by the comparator to determine the operating point, so that a more stable control operation can be performed.

According to the voltage generation circuit of the fourth aspect, in addition to the effect achieved by the voltage generation circuit of the third aspect, the transistor switch Q3 is controlled to be turned on and off by the output of the comparator, and the on resistance thereof has no problem in voltage drop. Low resistance,
Although the function of the parasitic diode D3 includes an offset of the forward voltage, even if an output abnormality occurs on any side of the transistor switch Q3, it is possible to converge, and it is advantageous for monolithic including this switch. .

According to the voltage generating circuit of the fifth aspect, in addition to the effect achieved by the voltage generating circuit of the second aspect, a diode is provided so that the switch means conducts from the output terminal toward the constant potential point. Therefore, although the offset amount corresponding to the forward voltage of the diode remains, the switch means is composed of only the diode, so that the circuit configuration is simple, the number of parts can be reduced, and the required area when integrated into an IC is reduced. be able to.

According to the voltage generating circuit of the sixth aspect, in addition to the effect achieved by the voltage generating circuit of the second aspect, the switch means is provided with an anti-parallel diode between the output terminal and the constant potential point. Therefore, although the offset amount corresponding to the forward voltage of the diode remains, the switch means is composed only of the diode, so that the circuit configuration is simple, the number of parts can be reduced, and the required area when integrated into an IC is reduced. Can be. Also, even if an output abnormality occurs on either side of the switch means, it can be quickly absorbed.

According to the voltage generating circuit of the seventh aspect, the same effect as that of the voltage generating circuit of the second aspect can be obtained.
By configuring the low input resistance constant voltage generating means with a chargeable battery or capacitor, excess charge can be absorbed. In particular, in the case of a rechargeable battery, the battery is charged by the charge absorbed by the battery, so that the excess charge that was originally wasted can be reused as battery energy, and energy saving can be achieved. .

According to the voltage generating circuits of the eighth, ninth, tenth, and eleventh aspects, the same effects as those of the third to sixth aspects can be obtained in addition to the effects of the voltage generating circuit of the seventh aspect. be able to.

According to the voltage generating circuit of the twelfth aspect, the basic operation and effect are the same as those of the second aspect, and the low input resistance constant voltage generating means is replaced by a high resistance resistance, N
Since the circuit is composed of the P-type output transistor, the high-resistance resistor, and the first error amplifier, the circuit configuration is easy because it is composed of the P-type transistor and the second error amplifier. Further, although it is related to the configuration of the switch means, all circuits can be configured by ordinary electronic circuit means, and it is easy to make it monolithic.

According to the voltage generating circuits of the thirteenth, fourteenth, fifteenth, and sixteenth aspects, the same effects as those of the third to sixth aspects can be obtained in addition to the effects of the voltage generating circuit of the twelfth aspect. be able to.

According to the voltage generating circuits of the seventeenth and eighteenth aspects, the forward voltage Vf of the diode as the switch means is provided.
The input of the reference voltage Vref from the internal reference voltage circuit is supplied to the inverting input terminal of the second error amplifier 2 via a diode in order to cancel the error component due to 1. Thereby, the drain voltage of the output transistor and
Since the voltage difference from the drain voltage of the transistor is kept equal to the forward voltage Vf1 of the diode as the switching means, the function limitation due to the forward voltage of the diode can be eliminated.

In addition, the effect of the diode according to the fifth or sixth aspect, that is, since the switch means is composed of only the diode, the circuit configuration is simple, the number of parts can be reduced, and an IC is realized. In this case, the required area can be reduced, or the switch means is composed of only diodes, so that the circuit configuration is simple, the number of parts can be reduced, and the required area in the case of an IC can be reduced. . Even if an output abnormality occurs on either side of the switch means, it is possible to converge as quickly as possible.

According to the voltage generating circuit of the nineteenth aspect, the same effects as those of the voltage generating circuit of the eighteenth aspect can be obtained.
By connecting the diode D1 and the second diode D2 via the fourth diode D4, the potential difference of the second diode D2 in the steady state is made equal to the forward voltage Vf1, so that the forward voltage of the diode D2 is used. Function restrictions can be eliminated.

A first conductivity type transistor Q4 connected in parallel to a series circuit of a gate resistor R2 'and a second resistor R2.
Is connected to the connection point between the gate resistor R2 'and the second resistor R2, the first conductivity type transistor Q4 is turned on only at the moment when the output voltage Vout temporarily drops below the set voltage, so that the time delay occurs. Therefore, a drop in the output voltage Vout can be suppressed.

According to the voltage generating circuit of the twentieth aspect, the same effect as that of the voltage generating circuit of the eighteenth aspect can be obtained.
By connecting the diode D1 and the second diode D2 via the fourth diode D4, the potential difference of the second diode D2 in the steady state is made equal to the forward voltage Vf1, so that the forward voltage of the diode D2 is used. Function restrictions can be eliminated.

The gate of the first conductivity type transistor Q4 connected in parallel with the second resistor R2 is connected to the gate resistor R4.
4. The first power supply terminal Vdd via the gate capacitor C4
And the output terminal, the first conductivity type transistor Q4 is more stably turned on only at the moment when the output voltage Vout temporarily drops below the set voltage without being affected by the fluctuation of the power supply voltage. The drop of the output voltage Vout can be suppressed without time delay.

According to the voltage regulator of the present invention, normally, the drain potential of the output transistor is compared with the internal reference voltage Vref by the error amplifier to a value corresponding to the voltage dividing ratio by the two high resistance resistors. And the output voltage is determined. The operation and effect of the transient phenomenon are the same as those of the voltage generating circuit according to claims 2 to 20. From this, the voltage regulators of claims 21 to 39 can achieve the same effects as the reference voltage generation circuits of claims 2 to 20.

The portable terminal device according to claim 40 is configured to include any one of the voltage generating circuits according to claims 2 to 20 or any one of the voltage regulators according to claims 21 to 39 as an internal power supply device. In addition, it is possible to secure a power supply that has a fast rise characteristic, excellent driving capability, good transient characteristics due to load fluctuations, a stable voltage, and low power consumption.

[Brief description of the drawings]

FIG. 1 is a diagram showing a reference voltage generation circuit according to a first embodiment of the present invention.

FIG. 2 is a characteristic diagram showing an operation state in the reference voltage generation circuit of the present invention.

FIG. 3 is a diagram showing a reference voltage generation circuit according to a second embodiment of the present invention.

FIG. 4 is a diagram showing drain potential response characteristics of each transistor in FIG. 3;

FIG. 5 is a diagram showing a reference voltage generation circuit according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a reference voltage generation circuit according to a fourth embodiment of the present invention.

FIG. 7 is a diagram showing a reference voltage generation circuit according to a fifth embodiment of the present invention.

FIG. 8 is a diagram showing a reference voltage generation circuit according to a sixth embodiment of the present invention.

FIG. 9 is a diagram showing a reference voltage generation circuit according to a seventh embodiment of the present invention.

FIG. 10 is a configuration diagram of a voltage regulator according to an eighth embodiment of the present invention.

FIG. 11 is a diagram showing a general configuration example of a conventional reference voltage generation circuit.

FIG. 12 is a diagram showing a configuration example of another conventional reference voltage generation circuit.

FIG. 13 is a diagram showing a configuration example of a conventional voltage regulator.

FIG. 14 is a characteristic diagram showing an operation state in a conventional reference voltage generation circuit.

[Explanation of symbols]

 Q1 P-type output transistor Q2 N-type transistor Q3, Q4 P-type transistor R1 to R3 Resistance (high resistance value) R11 to R22 Resistance (high resistance value) D1 to D4 Diode C Load capacitance 1,2 Error amplifier 3Comparator 4Low Input resistance constant voltage generating means 8 Internal reference voltage circuit 9 Load circuit 10 to 90 Reference voltage circuit 100 Voltage regulator

Claims (40)

[Claims] An output transistor and a resistor are connected in series between power supply terminals and output from the connection point to a load. The voltage at the connection point or a voltage obtained by dividing the voltage and an internal reference voltage are amplified by an error amplifier. Controlling the gate voltage of the output transistor to generate a constant voltage output voltage, wherein a low input resistance that generates a constant voltage equal to a target value of the output voltage with a low input resistance. Providing a constant voltage generating means, and connecting the connection point and the output of the low input resistance constant voltage generating means by a switch when a difference occurs between the voltage of the low input resistance constant voltage generating means and the output voltage. A voltage generation method characterized by the following. 2. An output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, an internal reference voltage applied to an inverting input, and an output terminal voltage applied to an output terminal. A first error amplifier input to the non-inverting input and having an output connected to the gate of the output transistor; low input resistance constant voltage generating means for forming a constant potential point of a constant voltage equal to the internal reference voltage with a low input resistance; Switch means connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. 3. The voltage generating circuit according to claim 2, wherein
A voltage generating circuit, wherein the switch means comprises a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. 4. The voltage generating circuit according to claim 3,
A switch which is driven by an output of the comparator is a transistor switch. 5. The voltage generating circuit according to claim 2,
A voltage generating circuit, wherein the switch means is a diode provided so as to conduct from an output terminal to a constant potential point. 6. The voltage generating circuit according to claim 2, wherein
A voltage generating circuit, wherein the switch means is a diode connected in anti-parallel. 7. An output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and a second power supply terminal, an internal reference voltage applied to an inverting input, and an output terminal voltage applied to an output terminal. A first error amplifier input to the non-inverting input and having an output connected to the gate of the output transistor; and a rechargeable battery or capacitor, having a low input resistance and forming a constant potential point of a constant voltage equal to the internal reference voltage. Low input resistance constant voltage generating means, connected between the output terminal and the constant potential point,
A switching unit that is turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. 8. The voltage generating circuit according to claim 7, wherein
A voltage generating circuit, wherein the switch means comprises a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. 9. The voltage generating circuit according to claim 8,
A switch which is driven by an output of the comparator is a transistor switch. 10. The voltage generation circuit according to claim 7, wherein the switch means is a diode provided so as to conduct from the output terminal to a constant potential point. 11. The voltage generating circuit according to claim 7, wherein said switch means is a diode connected in anti-parallel. 12. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, and an internal reference voltage connected to the inverted input. A first error amplifier having an output terminal voltage input to the non-inverting input and an output connected to the gate of the first conductivity type output transistor; a second resistor connected between the first power supply terminal and the constant potential point; A second conductivity type transistor connected between the constant potential point and the second power supply terminal, an internal reference voltage input to an inverting input, a constant potential point voltage input to a non-inverting input, and an output
A second error amplifier connected to the gate of the conductivity type transistor, and a switch connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. And a voltage generation circuit comprising: 13. The voltage generating circuit according to claim 12, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. A voltage generating circuit, characterized by: 14. The voltage generation circuit according to claim 13, wherein the switch driven by the output of the comparator is a transistor switch. 15. The voltage generating circuit according to claim 12, wherein the switch means is a diode provided so as to conduct from an output terminal to a constant potential point. 16. The voltage generating circuit according to claim 12, wherein the switch means is a diode connected in anti-parallel. 17. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, and an internal reference voltage connected to an inverting input. A first error amplifier having an output terminal voltage input to the non-inverting input and an output connected to the gate of the first conductivity type output transistor; a second resistor connected between the first power supply terminal and the constant potential point; A second conductivity type transistor connected between the constant potential point and the second power supply terminal, an internal reference voltage input to an inverting input via a diode, a constant potential point voltage input to a non-inverting input, and an output A second error amplifier connected to the gate of the type transistor, and connected between the output terminal and the constant potential point. When a difference occurs between the output terminal voltage and the constant potential point voltage, the output terminal connects to the constant potential point. Diode provided to conduct toward And a voltage generation circuit comprising: 18. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, and an internal reference voltage connected to the inverting input. A first error amplifier having an output terminal voltage input to the non-inverting input and an output connected to the gate of the first conductivity type output transistor; a second resistor connected between the first power supply terminal and the constant potential point; A second conductivity type transistor connected between the constant potential point and the second power supply terminal, an internal reference voltage input to an inverting input via a diode, a constant potential point voltage input to a non-inverting input, and an output A second error amplifier connected to the gate of the type transistor, connected between the output terminal and the constant potential point, and provided so as to conduct when a difference occurs between the output terminal voltage and the constant potential point voltage. And a diode connected in anti-parallel. A voltage generating circuit, characterized by: 19. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, and an internal reference voltage connected to an inverting input. A first error amplifier having an output terminal voltage input to the non-inverting input and an output connected to the gate of the first conductivity type output transistor; and a gate connected in series between the first power supply terminal and the constant potential point. A resistor, a second resistor R2 and a fourth diode conducting in the direction of the constant potential point from the first power supply terminal, and a gate connected to the gate resistor and the second resistor in series with a series circuit of the gate resistor and the second resistor. A first conductivity type transistor connected to the connection point; a second conductivity type transistor connected between the constant potential point and the second power supply terminal;
A second error amplifier having a constant potential point voltage input to the non-inverting input and a non-inverting input via a diode, and an output connected to the gate of the second conductivity type transistor, connected between the output terminal and the constant potential point A first diode provided to conduct from the output terminal to the constant potential point when a difference occurs between the output terminal voltage and the constant potential point voltage;
The second connection is made between the connection point of the diode and the output terminal.
A voltage generating circuit, comprising: a second diode provided so as to conduct from a connection point between the resistor and the fourth diode toward an output terminal. 20. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor connected between the output terminal and the second power supply terminal, and an internal reference voltage connected to the inverted input. An output terminal voltage is input to the non-inverting input, an output is connected to the gate of the first conductivity type output transistor, and a second error amplifier is connected in series between the first power supply terminal and the constant potential point. A resistor and a fourth diode conducting in a direction from the first power supply terminal toward the constant potential point; a fourth diode connected in parallel with the second resistor; a gate connected to the first power supply terminal via a gate resistor; A first conductivity-type transistor connected to a connection point between the second resistor and the fourth diode via a second resistor connected between the constant potential point and the second power supply terminal;
A conductive type transistor, a second error amplifier having an internal reference voltage input to an inverting input via a third diode, a constant potential point voltage input to a non-inverting input, and an output connected to the gate of the second conductive type transistor; A first diode connected between the output terminal and the constant potential point, and provided to conduct from the output terminal toward the constant potential point when a difference occurs between the output terminal voltage and the constant potential point voltage; , The second resistor and the fourth diode are connected between a connection point of the second resistor and the fourth diode and the output terminal.
A second diode provided so as to conduct from a connection point of the diode to an output terminal. 21. An output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage connected to an inverting input. A first error amplifier having a non-inverting input to a connection point voltage of the first and second resistors, and an output connected to the gate of the output transistor; and a constant voltage constant having a low input resistance and equal to the output voltage target value. Low input resistance constant voltage generating means for forming a potential point, and switch means connected between the output terminal and the constant potential point and turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. A voltage regulator comprising: 22. The voltage regulator according to claim 21, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. A voltage regulator characterized by the following. 23. The voltage regulator according to claim 22, wherein the switch driven by the output of the comparator is a transistor switch. 24. The voltage regulator according to claim 21, wherein the switch means is a diode provided so as to conduct from an output terminal to a constant potential point. 25. The voltage regulator according to claim 21, wherein the switch means is a diode connected in anti-parallel. 26. An output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage connected to an inverting input. , A connection point voltage of the first resistor and the second resistor is input to a non-inverting input, and a first error amplifier whose output is connected to the gate of the output transistor; and a rechargeable battery or a capacitor. A low input resistance constant voltage generating means for forming a constant potential point of a constant voltage equal to the reference voltage, and a connection between the output terminal and the constant potential point, when a difference occurs between the output terminal voltage and the constant potential point voltage And a switch means to be turned on. 27. The voltage regulator according to claim 26, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. A voltage regulator characterized by the following. 28. The voltage regulator according to claim 27, wherein the switch driven by the output of the comparator is a transistor switch. 29. The voltage regulator according to claim 26, wherein the switch means is a diode provided so as to conduct from an output terminal to a constant potential point. 30. The voltage regulator according to claim 26, wherein the switch means is a diode connected in anti-parallel. 31. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistance and a second resistance connected in series between the output terminal and the second power supply terminal, and an internal reference voltage. A first error amplifier having an inverting input, a connection point voltage of the first resistor and the second resistor input to a non-inverting input, and an output connected to the gate of the first conductivity type output transistor; a first power supply terminal; A third resistor, a fourth resistor, and a fifth resistor connected in series between the two power terminals; a second conductivity type transistor connected between a connection point of the third resistor and the fourth resistor and the second power terminal; A second error amplifier having a reference voltage input to the inverting input, a connection point voltage of the fourth resistor and the fifth resistor input to the non-inverting input, and an output connected to the gate of the second conductivity type transistor; Between the third resistor and the fourth resistor. A switching means that is turned on when a difference occurs between the output terminal voltage and the constant potential point voltage. 32. The voltage regulator according to claim 31, wherein the switch means includes a comparator to which an output terminal voltage and a constant potential point voltage are input, and a switch driven by an output of the comparator. A voltage regulator characterized by the following. 33. The voltage regulator according to claim 32, wherein the switch driven by the output of the comparator is a transistor switch. 34. The voltage regulator according to claim 31, wherein the switch means is a diode provided so as to conduct from an output terminal to a constant potential point. 35. The voltage regulator according to claim 31, wherein the switching means is a diode connected in anti-parallel. 36. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage. A first error amplifier having an inverting input, a connection point voltage of the first resistor and the second resistor input to a non-inverting input, and an output connected to the gate of the first conductivity type output transistor; a first power supply terminal; A third resistor, a fourth resistor, and a fifth resistor connected in series between the two power terminals; a second conductivity type transistor connected between a connection point of the third resistor and the fourth resistor and the second power terminal; A second error amplifier having a reference voltage input to the inverting input via a diode, a connection point voltage of the fourth resistor and the fifth resistor to the non-inverting input, and an output connected to the gate of the second conductivity type transistor; Terminals and third and fourth resistors serving as constant potential points And a diode connected between the output terminal and the constant potential point when a difference occurs between the output terminal voltage and the constant potential point voltage. Features a voltage regulator. 37. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage. A first error amplifier having an inverting input, a connection point voltage of the first resistor and the second resistor input to a non-inverting input, and an output connected to the gate of the first conductivity type output transistor; a first power supply terminal; A third resistor, a fourth resistor, and a fifth resistor connected in series between the two power terminals; a second conductivity type transistor connected between a connection point of the third resistor and the fourth resistor and the second power terminal; A second error amplifier having a reference voltage input to the inverting input via a diode, a connection point voltage of the fourth resistor and the fifth resistor to the non-inverting input, and an output connected to the gate of the second conductivity type transistor; Terminals and third and fourth resistors serving as constant potential points And a diode connected in anti-parallel and provided to conduct when a difference occurs between the output terminal voltage and the constant potential point voltage. regulator. 38. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage. Is connected to the inverting input, the voltage at the connection point of the first and second resistors is input to the non-inverting input, and the output is connected to the gate of the first conductivity type output transistor. A fourth diode connected in series between the potential point and the gate resistor, the third resistor, and the first power supply terminal in the direction of the constant potential point, and connected in parallel to a series circuit of the gate resistor and the third resistor; The gate is connected to the gate resistor and the third
A first conductivity type transistor connected to a connection point with the resistor, a second conductivity type transistor connected between the constant potential point and the second power supply terminal, and a series connected in parallel to the second conductivity type transistor , The internal reference voltage Vref is input to the inverting input via the third diode, the connection point voltage of the fourth and fifth resistors is input to the non-inverting input, and the output is the second conductive type. A second error amplifier connected to the gate of the transistor, connected between the output terminal and the constant potential point, and when a difference occurs between the output terminal voltage and the constant potential point voltage, the output terminal changes to the constant potential point. A first diode provided so as to conduct toward the output terminal, connected between a connection point of the third resistor and the fourth diode and the output terminal, and from the connection point of the third resistor and the fourth diode toward the output terminal. Second die provided to conduct Voltage regulator, characterized in that it comprises a chromatography de, a. 39. A first conductivity type output transistor connected between a first power supply terminal and an output terminal, a first resistor and a second resistor connected in series between the output terminal and the second power supply terminal, and an internal reference voltage. Is connected to the inverting input, the voltage at the connection point of the first and second resistors is input to the non-inverting input, and the output is connected to the gate of the first conductivity type output transistor. A third resistor connected in series between the third power supply and the potential point and a fourth power supply connected in the direction of the constant potential point from the first power supply terminal;
A diode connected in parallel to the third resistor, a gate connected to the first power supply terminal via a gate resistor, and a gate connected to a connection point of the third resistor and the fourth diode via a gate capacitor. A first conductivity type transistor, a second conductivity type transistor connected between the constant potential point and the second power supply terminal, a fourth resistance and a fifth resistance connected in parallel to the second conductivity type transistor, A second error amplifier having an internal reference voltage input to the inverting input via the third diode, a connection point voltage of the fourth resistor and the fifth resistor to the non-inverting input, and an output connected to the gate of the second conductivity type transistor And a first terminal connected between the output terminal and the constant potential point, and provided to conduct from the output terminal to the constant potential point when a difference occurs between the output terminal voltage and the constant potential point voltage. Diode and third resistor A second diode connected between the connection point of the fourth diode and the output terminal, and provided so as to conduct from the connection point of the third resistor and the fourth diode toward the output terminal. Voltage regulator. 40. A portable terminal device comprising a voltage generating circuit according to claim 2 or a voltage regulator according to claim 21 to 39 as a power supply device.