JPH0738141B2 - Voltage-stabilized integrated circuit device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a voltage stabilizing integrated circuit device in which a voltage stabilizing circuit is formed in a semiconductor integrated circuit device.

Configuration of the conventional example and its problems The voltage stabilizing circuit includes a reference voltage generating unit, an error voltage amplifying unit,
Comprised of a control element, error voltage detector, etc., the voltage of the error voltage detector that monitors the output voltage is compared with the reference voltage, and the output of the error voltage amplifier keeps the output of the control element constant and stable. The output voltage is obtained.

FIG. 1 shows a block diagram of a series control type voltage stabilizing circuit. In the figure, 1 is an error voltage amplifier, 2 is a control element, 3
Is an error voltage detector, 4 is a reference voltage generator, 5 is a constant current source, 6 is an input voltage terminal, 7 is an output voltage terminal, and 8 to
10 is a conducting wire. The error voltage amplification unit 1, the control element 2, and the error voltage detection unit 3 form a negative feedback loop.

In the circuit configuration of FIG. 1, when the reference voltage of the reference voltage generator is Vs, the detection resistors of the error voltage detector 3 are RΛ and RΒ, and the negative feedback loop gain is sufficiently large, the voltage is taken out to the output voltage terminal 7. The output voltage Vo is expressed by the following equation.

Vo = V _S (1 + RΒ / RΛ) (1) As is clear from the equation (1), the output voltage Vo is the detection resistance R
It can be set to any value higher than the reference voltage Vs by changing Λ and RΒ.

Many of the voltage stabilizers currently commercialized use this circuit type. Among them, the so-called three-terminal regulator has an output in which the values of the detection resistors RΛ and RΒ are fixed. It is a fixed voltage type voltage stabilizing circuit device.

By the way, the value of the output voltage set by such a voltage stabilization circuit is set in advance to the value of the power supply voltage that is often adopted in general electronic equipment, and therefore, in many electronic equipment, the existing voltage stabilization is used. It is considered that there is no problem even if the integrated circuit device is used. However, in some electronic devices, since a desired power supply voltage cannot be obtained by an off-the-shelf product, it is often the case that an off-the-shelf product that outputs a fixed output voltage within a range that does not hinder the circuit operation is selected and used. For example,
Output voltage of commercially available 3-terminal regulator is 5 (V), 8
Among ready-made products of (V), 12 (V), 15 (V), and 24 (V), for example, in the case of an electronic device with a power supply voltage of 9 (V), allow 12 ( V) supply voltage had to be used, which was undesired as it would consume undesired power.

In recent years, the voltage stabilizing circuit is also often configured by a semiconductor integrated circuit device. In this case, it is easy to form a plurality of desired resistors on a semiconductor chip and set a predetermined resistance ratio in advance. Therefore, it is suitable for a circuit configuration in which a desired output voltage is set by a resistance ratio like the present circuit device.

FIG. 2 shows a circuit configuration diagram in which a plurality of detection resistors for setting a plurality of output voltages, in particular, ones corresponding to the detection resistors R B are provided in advance. For example, the resistance value is 0 (K
Ω), 3 (KΩ), 7 (KΩ), 10 (KΩ), 19 (KΩ), if five kinds of detection resistors R B are prepared, one or more of these resistors are selected, A desired output voltage can be obtained.

Here, the reference voltage Vs = 5 (V) and the detection resistor RΛ = 5 (K
Under the conditions set to (Ω), if the detection resistance R B is set to the (B) side, that is, R B = 7 (KΩ), the output voltage
For Vo, Vo = 12 (V) can be obtained from the above equation (1). Similarly, the detection resistance R B is 0 (KΩ), 3 (KΩ), 10 (KΩ),
When 19 (KΩ) is selected, the output voltage Vo is 5 (V) and 8 respectively.
It can be easily understood that it will be (V), 15 (V), 24 (V).

FIG. 3 is a resistor layout diagram in which the portions corresponding to the detection resistors RΛ and RΒ in FIG. 2 are placed on the semiconductor chip. The resistor R ₁ in FIG. 3 corresponds to the resistor R Λ in FIG. ₂ , and the resistors R ₂ , R ₃ , R ₄ , R ₅ a, R ₅ b in FIG. Corresponds to the resistance R B. Then, R ₂ = 3 (KΩ) and R ₃ = 7, respectively, so that the resistance value of the detection resistor R B in FIG. 2 is satisfied.
(KΩ) and R ₄ = 10 (KΩ) are set, R ₅ a and R ₅ b are connected in series, and R ₅ a + R ₅ b = 19 (KΩ) is selected.
Also, 80, 90, 100 in FIG. 3 are the lead wires 8, 9, 1 in FIG. 2, respectively.
It is a wiring unit corresponding to 0.

In FIG. 3, when the detection resistance R B = 7 (KΩ) is set, the wiring points A and A ′ may be connected. Similarly, the detection resistance RΒ = 3 (KΩ), 10 (KΩ), 19 (KΩ)
When set to, point B and point B ', point C and point C', respectively.
It suffices to connect the points D, D and D '. The detection resistance R
It is not necessary to individually use the resistors R ₂ , R ₃ , R ₄ , R ₅ a + R ₅ b as B, and it is naturally possible to use these resistors in combination. For example, resistors R ₂ (3KΩ) and R ₃
A parallel body of (7KΩ) may be used. In this case, the value of the detection resistor R B is 2.1 (KΩ), and the output voltage Vo is Vo = 7.1 (V) from the above equation (1).

By the way, when an electric element is formed on a semiconductor chip, there is a contact resistance in the opening 11 where the diffusion layer and the wiring portion contact, and the resistance value of this contact resistance Rc is the opening.
It is known to depend on the size of 11 and the impurity concentration of the diffusion layer. Therefore, this contact resistance Rc cannot be ignored when a circuit device that requires high precision is integrated. This similarly poses a problem in the present circuit device that determines the output voltage by the resistance ratio, and it is not preferable to simply adopt the above equation (1) when setting the output voltage Vo. That is, in order to set the strict output voltage Vo, the following equation in consideration of the contact resistance Rc must be used.

Next, in order to clarify how the contact resistance Rc contributes to the output voltage Vo, the output voltage Vo obtained by the equations (1) and (2) is shown in the table below.

When calculating the above numerical values, for example, the contact resistance per unit is 75 (Ω), the contact resistance Rc
= 150 (Ω), and when RΒ = 19 (KΩ), the resistor R ₅ a
And R ₅ b so connected in series with, and the contact resistance with the 300 (Omega).

As is clear from the above table, the output voltage Vo in the case of considering the contact resistance Rc is the boundary of the condition of RΛ = RΒ, that is, the boundary of RΒ = 5 (KΩ) in the above conventional example.
It can be understood that the output voltage Vo becomes larger than the set value X as the value becomes smaller, and conversely, the ratio (Y / X) to the set value becomes smaller as the R Β becomes larger. This means that the output voltage Vo is not accurately set as designed, which is extremely inconvenient.

An object of the present invention is to provide a stabilized voltage integrated circuit device which overcomes the above-mentioned inconvenience, that is, an output voltage is set accurately. Furthermore, another object is to provide a circuit device capable of outputting a wide range of output voltages in predetermined steps.

Configuration of the Invention The present invention is essentially configured by connecting a plurality of unit resistors (R _{11 to} R ₂₂ ) having the same resistance shape and value including an opening in series between the output end (7) and the reference potential point. The error voltage detecting unit (3) for dividing the output voltage is compared with the voltage divided by the error voltage detecting unit and the reference voltage generated by the reference voltage generating unit (4), and the compared error voltage is calculated. An error voltage amplification section (1) for amplification, and a control element which is supplied with power from an input voltage terminal (6) and outputs a stabilized output voltage controlled by the output of the error voltage amplification section to the output terminal (7). (2) A circuit device in which the output terminal, the error voltage detection unit, the error voltage amplification unit, and the control element form a negative feedback loop, and is integrated on a semiconductor substrate, wherein the unit resistance is The error voltage detection unit ( ) Is defined, the voltage-stabilized integrated circuit device is characterized in that according to this configuration, the influence of the contact resistance Rc of the opening is eliminated as a detection error of the error voltage detector (3), The error of the feedback amount can be eliminated, and the stabilized output voltage can be set accurately in a wide range.

Description of Embodiments FIG. 4 shows an embodiment of the present invention, and is a resistor layout diagram in which a plurality of unit resistors used in the error voltage detector 3 are arranged on a semiconductor chip. Those having the same functions as those in FIG. 3 are designated by the same reference numerals.

The resistors R _{11 to} R _{34 in} FIG. 4 have the same shape and the same resistance value, for example, are selected to be approximately 1 (KΩ), and 24 resistors are arranged close to each other on the same chip. This is based on the fact that integrated elements that require matching preferably have the same shape and size and are in close proximity when placed in an integrated circuit device.

Next, the effect of the contact resistance Rc in one embodiment of the present invention will be described. Now, the unit resistances R ₁₁ to R ₃₄ and the shape of the body are the same, the body resistance is Ro, the contact resistance is Rc, and the number of unit resistances connected in series to form the detection resistance RΛ is n. , M is the number of unit resistors connected in series to form the detection resistor R B, the output voltage
Vo can be expressed by the following equation.

As is clear from the above formula (3), the contact resistance of the opening 11
Even if Rc is a size that cannot be ignored compared to the resistance Ro of the body, the absolute value of the contact resistance Rc does not contribute to the relative ratio of resistance, and the output voltage Vo depends on the size of the contact resistance Rc. It can be understood that it is determined by the number ratio of the unit resistance without causing

Next, a procedure for producing a wide range of output voltages will be described. First, to set the detection resistance RΛ = 5 (KΩ),
For example, five resistors R _{11 to} R ₁₅ are connected in series. Then, 19 resistors R ₁₆ to R ₃₄ are used as the detection resistor R B by a desired connection. And resistors R _{16 to} R
_{If 34} are used in series connection, the detection resistor R B is
It can be set from 1 (KΩ) to 19 (KΩ) in steps of 1 (KΩ). At this time, including the case of the detection resistor R = 0, the output voltage Vo can be calculated from the formula (3) to a total of 20 in steps of 1 (V) from Vo = 5 (V) to Vo = 24 (V).
Different types of output voltages are available.

Moreover, in the integrated circuit device of the present invention, although the output voltage in a very wide range can be taken out, the area occupied by the resistance element for detection on the semiconductor chip is the same as that of the conventional example shown in FIG. There is also an advantage that you can. This is
Region X of the dotted line frame shown by the same area in FIG. 3 and FIG.
It is obvious by comparing the resistance element groups arranged inside.
When an unused unit resistance is generated in the embodiment shown in FIG. 4, if the opening of the unused unit resistance is covered with the wiring section 110, the quality problem is not necessary.

Furthermore, in the present embodiment, when switching to an output voltage other than the predetermined voltage, it is not necessary to start over from the first diffusion step, and it is possible to deal with it by changing the wiring mask. It is advantageous in that the photomask can be shared, and the photomask management and the slice in the process of diffusion are managed.

As described above, in the voltage-stabilized integrated circuit device of the present invention, the stabilized output voltage is set by the number ratio of the unit resistors connected in series, and the contact resistance of the opening does not affect the output voltage at all. It has a special effect.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a series control type voltage stabilizing circuit, FIG. 2 is a standard block configuration diagram of a voltage stabilizing circuit configured to take out a plurality of output voltages, and FIG. 3 is FIG. FIG. 4 shows a resistor layout diagram of a conventional example in which the error voltage detector is integrated in a semiconductor, and FIG. 4 is a resistor layout diagram of the error voltage detector according to an embodiment of the present invention. 1 ... Error voltage amplification section, 2 ... Control element, 3 ... Error voltage detection section, 4 ... Reference voltage generation section, 5 ... Constant current source, 6
...... Input voltage terminal, 7 …… Output voltage terminal, 8 to 10 …… Lead wire, 11 …… Opening part, 80,90,100,110 …… Wiring part, RΛ, R
B: Detecting resistance, R _{1 to} R ₄ , R _{11 to} R ₃₄ ...... Resistance element, R ₅ a, R ₅ b
...... Resistor.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-53-81931 (JP, A) JP-A-58-100449 (JP, A) Practical application Sho-57-78653 (JP, U)

Claims (1)

[Claims] 1. An error voltage detection unit configured to connect a plurality of unit resistors having the same resistance shape and value including an opening in series between an output end and a reference potential point to divide an output voltage. An error voltage amplification unit that compares the voltage divided by the error voltage detection unit with the reference voltage generated by the reference voltage generation unit and amplifies the compared error voltage. A control element that outputs a stabilized output voltage controlled by the output of the voltage amplification section to the output terminal, the output terminal, the error voltage detection section, the error voltage amplification section, and the control element form a negative feedback loop. At the same time, the voltage stabilized integrated circuit device is a circuit device integrated on a semiconductor substrate, wherein the voltage division ratio of the error detection unit is determined by the ratio of the numbers of the unit resistors connected in series.