KR100915151B1 - Reference Voltage Generating Circuits with Noise Immunity - Google Patents

Abstract

 The reference voltage generator circuit includes a reference voltage generator and an amplifier. The reference voltage generator includes a first current path and a second current source having a first current source, wherein one end of the first current source and one end of the second current source are commonly coupled to an internal power supply voltage corresponding to the first power supply voltage. It includes a second current path having a. The amplifier includes an amplifier having a differential amplifier structure receiving the first power supply voltage and negatively feeding back an internal power supply voltage corresponding to the first power supply voltage through the first current source and the second current source, respectively. The amplifier receives the voltage at the other end of the first current source to the inverting input terminal, receives the other end of the second current source to the non-inverting input terminal, and according to the virtual ground characteristics at the inverting input terminal and the non-inverting input terminal. The voltage between both ends of the first current source and the voltage between both ends of the second current source are substantially the same so that the first current provided through the first current path and the second current provided through the second current path are substantially the same. The internal supply voltage, which is the output of the differential amplifier, is negatively fed back to the differential amplifier and the virtual ground characteristics of the differential amplifier can be used to provide a reference voltage generator circuit that is robust against noise and enables low power design.

Description

Reference Voltage Generating Circuits with Noise Immunity

The present invention relates to a reference voltage generator circuit, and more particularly, to a reference voltage generator circuit resistant to noise.

A band gap reference circuit is a circuit that always generates a constant reference voltage regardless of temperature and external voltage in the system.

High precision reference voltages are widely used in a variety of circuits and systems, such as data converters, data acquisition systems, voltage regulators, and most measurement equipment.

In such application circuits and systems, it is required to design reference voltages so that they have a constant value and are not affected by changes in process parameters even when the temperature or supply voltage changes.

1 is a circuit diagram showing a conventional reference voltage generating circuit. Referring to FIG. 1, a conventional reference voltage generator circuit includes a reference voltage generator 10 and an amplifier 20. The transistors M9, M10, M12, M13, M15, M16, M17, and M18 are self bias circuits. Transistors M2, M4, M5, M6, M7, M8 operate as amplifiers, and transistors M1 and M2 supply bias current.

Referring to the operation of the reference voltage generating circuit of Figure 1 as follows.

Since the transistor M9 has the same voltage as the gate and the drain, the transistor M9 satisfies the saturation region operating condition of Equation 1 and operates in the saturation region.

Here, Vsd is the source-drain voltage of the MOS transistor, Vsg is the source-gate voltage of the MOS transistor, and | Vthp | is the threshold voltage for turning on the MOS transistor. Therefore, the drain current Id of the transistor M9 can be obtained by the following equation.

here, Is the mobility of the charge carriers, Is the capacitance per unit area of the gate oxide of the MOS transistor, W is the channel width of the MOS transistor, L is the channel length of the MOS transistor, Denotes a relative change in channel length with respect to the Vsd change as a channel length modulation coefficient.

Of transistors M9 and M10 , , , Vthp |, and Vsd are the same, the transistors M9 and M10 are current mirror structures, and the drain currents Id are the same because the gates of the transistors M9 and M10 are commonly connected to each other, and Vsg is the same. Similarly, transistors M17 and M18 are current mirror structures, and drain currents are the same. As such, the drain current is copied from transistor M9 in the left current path to transistor M10 in the right current path and from transistor M18 in the right current path to transistor M17 in the left current path and repeats as a result of the left current path and today's current path. The currents are equal to each other with Id. Since the currents in both current paths are the same, the Vgs voltages of the transistors M17 and M18 are the same, so the source voltage Vs17 (the voltage of the node N11) of the transistor M17 and the source voltage Vs18 (the node N21) of the M18 are the same. Therefore, the resistance (R1) at both ends of the equation (3) Veb takes

Veb = Veb2-Veb1

Where Veb is the voltage between the emitter and base of the bipolar transistor. The collector current Ic of the bipolar transistor is obtained by the following equation (4).

Here, Vt is a thermal voltage of about 25 mV at room temperature. Is is proportional to the number of bipolar transistors connected in parallel with saturation current. Veb from Equation 4 may be obtained by Equation 5 below.

Therefore, ΔVeb may be expressed by Equation 6 below.

Veb = Veb2-Veb1 = - =

Therefore, the resistor R1 Current (Id) flows. The current Id flows into the self bias circuits M9, M10, M12, M13, M15, M16, M17, M18 and is radiated through the transistor M9 to the transistor M11 by the current mirror structure.

The reference voltage Vref can be obtained by Equation 7 below.

In Fig. 1, transistors M2, M4, M5, M6, M7, and M8 are differential amplifiers, with the gate of transistor M8 being the inverting (-) input terminal and the gate of transistor M7 being the non-inverting (+) input terminal. The differential amplifier prevents the internal power supply Vreg of the reference voltage generator circuit from shaking.

Specifically, when the first power supply voltage VDD decreases due to noise, the internal power supply voltage Vreg decreases, and the drain voltage of the transistor M9 and the drain voltage of the transistor M12 decrease. Since the input voltage (VN) of the inverting input stage of the differential amplifier has decreased, the internal supply voltage Vreg, which is the output of the differential amplifier, increases, resulting in negative feedback that initially suppresses the decrease in the internal supply voltage Vreg due to noise. . Thus, the differential amplifier of the conventional reference voltage generating circuit of FIG. 1 operates to suppress the influence of external noise.

The current Id flowing in the transistor M6 of the differential amplifier is radiated to the transistor M3 through the current mirror structure. The current radiated to the transistor M3 flows to the transistor M1 and is radiated back to the transistor M2 through the current mirror structure, and the transistor M2 can supply an appropriate current to the reference voltage generation circuit.

The transistors M12, M13, M14, and M8 have a current mirror structure in which the same current Id flows.

The gate of transistor M8 and the gate of transistor M7 have the same voltage as the virtual ground characteristic of the differential amplifier input. In other words, the transistors M8 and M7 form a current mirror structure. Therefore, the same current Id flows through the transistors M12, M13, M14, M8, and M7. By using the current mirror structure as described above, if the current flowing through the transistor M2 is made to be 7 times the current flowing through the transistor M12, an appropriate current can be supplied to the reference voltage generating circuit.

Hereinafter, the problem of the conventional reference voltage generator circuit of FIG. 1 will be described.

Vgs to Turn-On a MOS Transistor in FIG. The minimum value of the first power supply voltage VDD for operating the transistors M9, M10, M12, M13, M15, M16, M17, and M18 constituting the self-biasing circuit in the saturation region is equal to Vth. same.

VDD (min) = Veb2 + Vgs18 + Vgs16 + Vsg12 + Vsg9 + Vov2

Where Veb is the emitter-to-base voltage of the bipolar transistor, Vgs is the gate-to-source voltage of the NMOS transistor, and Vsg is the source-to-gate voltage of the PMOS transistor. Vov2 is the overdrive voltage of transistor M2, Corresponds to the minimum Vsd value in Equation 9 below.

Vov = Vsg-| Vthp |

When current is radiated using the current mirror structure, the two transistors that make up the current mirror , , Assuming that | Vthp | and Vsd are equal, not only Vsg but also Vsd must be equal so that current is more accurately copied. In the conventional reference voltage generating circuit of FIG. 1, the current mirror is made of cascode to equalize Vsd of two transistors M9 and M10 constituting the current mirror. In addition, the transistors M12 and M13 were used to make the Vsds of the transistors M9 and M10 the same. Similarly, the transistors M15 and M16 were used to make the Vsds of the transistors M17 and M18 the same.

Therefore, the conventional reference voltage generator of FIG. 1 is a self-biased circuit having a cascode structure in which transistors are stacked in series, so the minimum value VDD (min) of the first power supply voltage becomes very high, which is not suitable for low power design. not.

Meanwhile, in order to generate the reference voltage Vref in FIG. 1, when a voltage equal to Equation 6 is applied across R1, the resistance R1 is applied across the resistor R1. Current flows. In the conventional reference voltage generating circuit of FIG. 1, the bipolar transistors Q1, Q2 and Q3 are necessary because the current flowing across R1 is copied to a current mirror to flow to the resistor R4 and the bipolar transistor Q3 to generate the reference voltage Vref.

Accordingly, it is a first object of the present invention to provide a reference voltage generator circuit that is resistant to external noise and suitable for a low power design.

The reference voltage generating circuit according to an aspect of the present invention for achieving the first object of the present invention is a first current path and a second current source having a first current source, wherein one end and the second current source of the first current source A reference voltage generator including a second current path having one end commonly coupled to an internal power supply voltage corresponding to the first power supply voltage, and receiving the first power supply voltage to correspond to the first power supply voltage. An amplifier having a differential amplifier structure in which an internal power supply voltage is negatively fed back through the first current source and the second current source, respectively, wherein the amplifier receives the voltage at the other end of the first current source through an inverting input terminal, The other end of the second current source is input to a non-inverting input terminal, and both ends of the first current source according to a virtual ground characteristic at the inverting input terminal and the non-inverting input terminal. By the pressure and the both-end voltage of the second current source is substantially equal to the second current provided to the first current and the second current path provided by the first current path is substantially equal. The reference voltage generator may provide a voltage of the non-inverting input terminal as a reference voltage. The first current path may further include a transistor having a voltage between the first current electrode and the control electrode which decreases with temperature. The first current path may further include a circuit element for amplifying a voltage, which increases with temperature, between the first current source and the transistor at a predetermined resistance ratio. The first current path includes a first resistance element having one end coupled to the other end of the first current source, a second resistance element having one end coupled to the other end of the first resistance element, and coupled with the other end of the second resistance element. The first transistor may include a first current electrode, a control electrode coupled to a second power supply voltage, and a second current electrode coupled to the second power supply voltage. The second current path may include a third resistance element having one end coupled to the other end of the second current source, a first current electrode coupled with the other end of the third resistance element, a control electrode coupled with the second power supply voltage, and It may include a second transistor having a second current electrode coupled to the second power supply voltage. The second resistor element and the third resistor element may have the same resistance value. The voltage between the first current electrode and the control electrode of the first transistor may decrease with temperature. The amplifier includes a third transistor having a first current electrode coupled to the first power supply voltage, a first current electrode coupled to the first power supply voltage, a control electrode connected to the control electrode of the first transistor, and the control. A fourth transistor having a second current electrode connected to the electrode, a first current electrode coupled to the second current electrode of the third transistor, a fifth transistor having a control electrode coupled to the inverting input terminal, and the fifth A first current electrode coupled to a first current electrode of the transistor, a sixth transistor having a control electrode coupled to the non-inverting input terminal, a first current electrode coupled to a second current electrode of the fifth transistor, and the A seventh transistor having a control electrode coupled with a first current electrode, a second current electrode coupled with the second power supply voltage, and a first electric field coupled to the second current electrode of the sixth transistor; An eighth transistor having an electrode, a control electrode connected to a control electrode of the seventh transistor, a second current electrode coupled to the second power supply voltage, a first current electrode coupled to a second current electrode of the fourth transistor, A ninth transistor coupled to a first current electrode of the eighth transistor and having a control electrode coupled to the first current electrode through a compensation resistor and a compensation capacitor, and a second current electrode coupled to the second power supply voltage; A tenth transistor having a first current electrode coupled to a second current electrode of a third transistor, a control electrode coupled to a control electrode of the seventh transistor, and a second current electrode coupled to the second power supply voltage. Can be. The current flowing through the ninth transistor may have a current value of k (k is a positive real number) times the first current provided to the first current path to maintain the virtual ground characteristic. In order to maintain the virtual ground characteristic of the amplifier, a two-stage amplification operation may be performed using the seventh transistor, the eighth transistor, and the ninth transistor.

In addition, the reference voltage generating circuit according to another aspect of the present invention for achieving the first object of the present invention includes: i) a first current source having one end coupled to an internal power supply voltage, a first resistor coupled to the other end of the first current source; A second resistance element having one end coupled to the other end of the first resistance element, a first current electrode coupled with the other end of the second resistance element, a control electrode coupled with a second power supply voltage, and the second power supply voltage; A first current path having a first transistor having a coupled second current electrode, ii) a second current source having one end coupled to the internal power supply voltage, a third resistance element having one end coupled to the other end of the second current source, A second current path having a first transistor coupled to the other end of the third resistance element, a control electrode coupled to the second power supply voltage, and a second transistor having a second current electrode coupled to the second power supply voltage; Including reference voltage And a booster having a differential amplifier structure receiving the first power supply voltage and negatively feedbacking an internal power supply voltage corresponding to the first power supply voltage through the first current source and the second current source, respectively. The amplifier receives the voltage at the other end of the first current source to the inverting input terminal, receives the other end of the second current source to the non-inverting input terminal, and according to the virtual ground characteristics at the inverting input terminal and the non-inverting input terminal. The voltage between both ends of the first current source and the voltage between both ends of the second current source are substantially the same so that the first current provided through the first current path and the second current provided through the second current path are substantially the same.

As described above, according to the reference voltage generating circuit of the present invention, in order to compensate for the disadvantage that the reference voltage generating circuit, which constitutes a self bias circuit with a cascode structure in which a conventional transistor is stacked in series, is not suitable for low power design. Instead of using a current mirror with a cascode structure, the internal supply voltage, which is the output of the differential amplifier, is negatively fed back into the differential amplifier, and the low-power design is possible using the virtual ground characteristics of the differential amplifier.

In addition, the reference voltage generator circuit of the present invention can reduce the influence of noise coming through the internal power supply voltage on the power supply voltage line by negative feedback of the internal power supply voltage, which is the output of the differential amplifier, to the differential amplifier.

1 is a circuit diagram showing a conventional reference voltage generating circuit.

2 is a reference voltage generator circuit according to an embodiment of the present invention.

3 is a graph showing a simulation result of a change in the reference voltage according to the temperature change by using the reference voltage generating circuit according to an embodiment of the present invention.

4 is a graph illustrating a simulation result of a power supply voltage variation removal ratio (PSRR) according to a frequency change using a reference voltage generator circuit according to an exemplary embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

100: reference voltage generator 110: first current path

120: second current path 200: amplifier

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, the same reference numerals will be used for the same means regardless of the reference numerals in order to facilitate the overall understanding.

The reference voltage generator circuit provides a constant voltage inside the integrated circuit (IC) that is not affected by changes in temperature, process, and power supply voltage. In particular, since noise enters the power supply voltage line, only the power supply voltage of the reference voltage generator circuit needs to be strongly isolated from the noise.

2 is a reference voltage generator circuit according to an embodiment of the present invention.

Referring to FIG. 2, a reference voltage generator circuit according to an embodiment of the present invention includes a reference voltage generator 100 and an amplifier 200.

The reference voltage generator 100 includes a first current path 110 and a second current path 120. The first current path 110 may include a transistor T9 operating as a first current source, a resistor R2 connected to the drain of the transistor T9, a resistor R1 connected in series with the resistor R2, and a bipolar transistor Q1 connected to one end of the resistor R1. The second current path 120 may include a transistor T10 operating as a second current source, a resistor R3 connected to the drain of the transistor T10, and a bipolar transistor Q2 connected to one end of the resistor R3.

The amplifier 200 has a differential amplifier structure. That is, the VN node, which is the gate of the transistor T8, corresponds to the inverting input terminal ((-) input terminal) of the differential amplifier, and the VP node, which is the gate of the transistor T7, corresponds to the non-inverting input terminal ((+) input terminal).

The amplifier 200 further includes transistors T5, T6, and T4 that perform two-stage amplification. Transistors T5 and T6 perform a single stage amplification function, and the drain terminal of transistor M5 provides a single stage amplified voltage. Transistor T4 performs a two stage amplification function. In an embodiment of the present invention, a structure in which two-stage amplification is used using transistors T5, T6, and T4 to maintain the virtual ground characteristics of the amplifier 200 is used. However, if amplification ratio of a predetermined value or more for maintaining the virtual ground characteristic of the amplifier 200 can be provided, a structure other than the two-stage amplifying structure using the transistors T5, T6, and T4 of FIG.

The amplifier 200 further includes transistors T1, T3, and T2 for supplying a bias current. Transistor T2 operates in the saturation region to supply the same current I through the first current path 110 and the second current path 120, and maintains a virtual ground characteristic. 'Supply. The current I 'supplied to the drain of the transistor M4 is k (k is a positive real number) of the current I provided to the first current path 110 (or the second current path 120) to maintain the virtual ground characteristic. ) Can have a current value of twice. For example, k can be two.

The reference voltage generating circuit according to an embodiment of the present invention does not use a cascode structure current mirror to compensate for the disadvantages of the conventional reference voltage generating circuit of FIG. 1, and uses an internal power supply voltage that is an output of a differential amplifier. Negative feedback of Vreg to the differential amplifier and the first power supply voltage VDD by equalizing the Vsd of the two current sources T9 and T10 of the reference voltage generator 100 using the virtual ground characteristics of the differential amplifier input stage. Low power design is possible by lowering the minimum value of.

Creating a negative feedback loop with the internal supply voltage Vreg, the output of the differential amplifier, as a differential amplifier results in a virtual grounding phenomenon in which the two input voltages of the differential amplifier, the negative input voltage VN and the positive input voltage VP, are equal. In FIG. 2, when the drain voltage (node N1 voltage) of the transistor T9 is connected to the inverting input terminal of the differential amplifier, and the drain voltage (node N2 voltage) of the transistor T10 is connected to the non-inverting input terminal of the differential amplifier, the transistors T9 and T10 are connected. The drain voltages are the same so that the Vsd of the transistors T9 and T10 are the same.

To turn on the MOS transistor in FIG. 2, Vgs Since it should be Vth, the minimum value of the first power supply voltage VDD for operating both the transistors T9 and T10 in the saturation region is expressed by Equation 10 below.

VDD (min) = Veb1 + V (R1) + V (R2) + Vsg9 + Vov2

Where Veb1 is the voltage between the emitter and base of bipolar transistor Q1, V (R1) is the voltage drop across resistor R1, V (R2) is the voltage drop across resistor R2, and Vgs9 is the gate and source of NMOS transistor T9. Is the voltage, and Vov2 is the overdrive voltage of the transistor T2, such as Vsg2-| Vthp |

Since the minimum value of the first power supply voltage VDD obtained as described above has a value smaller than the minimum value of the first power supply voltage VDD obtained by the reference voltage generator having the cascode structure of FIG. 1, a low power design is possible.

The reference voltage generating circuit according to an embodiment of the present invention cancels each other by adding a voltage that increases with temperature and a voltage that decreases with temperature to make a constant reference voltage even when the temperature changes.

In FIG. 1, a voltage increasing with temperature corresponds to a Veb difference ΔVeb between two bipolar transistors Q1 and Q2, and a voltage decreasing with temperature corresponds to Veb1 of a bipolar transistor Q1. ΔVeb can be obtained from the following equation (11).

ΔVeb = Veb2-Veb1

Here, Veb2 is the voltage between the emitter and the base of the bipolar transistor Q2, and Veb1 is the voltage between the emitter and the base of the bipolar transistor Q1.

Although the bipolar transistor Q1 is used in the reference voltage generating circuit according to an embodiment of the present invention, any circuit device having a voltage characteristic that decreases with temperature may be implemented as another circuit device. For example, instead of the bipolar transistor Q1, a PMOS transistor operating in a weak inversion region may be used.

The reference voltage generating circuit according to an embodiment of the present invention generates a reference voltage Vref by amplifying with a resistance ratio because the increase rate of? Veb is relatively small.

Assuming that R2 = R3, the voltage at node N1 is equal to the voltage at node N2, and the current I flowing through resistor R2 and the current I flowing through resistor R3 are the same, so that the voltage at node N3 and the voltage at node N4 are the same. Here, the reference voltage Vref is equal to the node N2 voltage, and the voltage of the node N2 is the same as the voltage of the node N1 according to the virtual ground characteristics, so the reference voltage Vref is equal to the voltage of the node N1.

Therefore, ΔVeb is expressed by equation (6). ΔVeb is across R1, so the current flowing through R1 Is obtained by the following equation (12).

Is copied from T9 to T10 through the current mirrors of transistors T9 and T10.

In the reference voltage generator circuit according to the exemplary embodiment of the present invention, a resistor R2 is directly connected to R1 as shown in FIG. 2 without using a current mirror having a cascode structure as shown in FIG. By amplifying to generate the reference voltage Vref (= node N1), bipolar transistors Q1 and Q2 can be implemented.

Here, in the reference voltage generation circuit according to the exemplary embodiment of FIG. 2, the reference voltage Vref may be amplified by a predetermined resistance ratio by amplifying a voltage ΔVeb increasing with the temperature using two resistors R1 and R2, for example. However, instead of using two resistors R1 and R2, it is possible to implement other circuit elements that can generate a reference voltage Vref by amplifying at a predetermined ratio.

In the reference voltage generating circuit according to an embodiment of the present invention, the reference voltage Vref may be obtained by the following equation (13).

3 is a graph showing a simulation result of a change in a reference voltage according to a temperature change using a reference voltage generating circuit according to an embodiment of the present invention, and FIG. 4 is a reference voltage generating circuit according to an embodiment of the present invention. This is a graph of simulation of power supply voltage variation removal ratio (PSRR) according to frequency change.

The simulation was verified by computer simulation (HSPICE) using CMOS 0.18um process parameters. In FIG. 2, resistors R1, R2, and R3 used P + GPOLY (without CoSix), 1 Primary temperature coefficient, TC1 = -266 X, representing the change in resistance with each change Of , Secondary temperature coefficient TC2 = 1.1 X Of It was. Here, the resistance value R (t) according to the temperature is obtained by the following equation (14).

Here, the resistor R represents a sheet resistance value of the resistors R1, R2 or R3 of FIG. 2.

In addition, the value of each circuit element was R1 = 22.4kV, R2 = R3 = 190.4KV, Rc = 24KV, Cc = 2.7pF, m (Q1) = 8, m (Q2) = 1. Here, m represents the number of bipolar transistors connected in parallel. The current I flowing through the drain of transistor T9 is 2.5uA, radiated to transistor T10, the current I flowing through the drain of transistor T8 is 2.5uA, the current I flowing through the drain of transistor T7 is 2.5uA, and the current flowing through transistor T4 is 5uA. (The total current flowing through the transistors T7, T8, and T4 of the amplifier 200 is 10 uA.).

As shown in FIG. 3, the reference voltage Vref was about 1.157 V (condition: VDD = 2.3 Volt, temperature T = 25 ° C.), and the temperature was −20. To 120 When it was changed between them, there was a change of 1.366 mV from 1.156909 Volt to 1.158275 Volt, and it was found that there was almost no change in the reference voltage according to the temperature change.

As shown in Figure 4, VDD = 3.3 Volt, temperature T = 25 , The power supply voltage fluctuation removal ratio PSRR is 65dB under the condition that the frequency (Freqency) is 100 Hz, indicating that there is almost no difference between the reference voltage generating circuit and the power supply voltage fluctuation removal ratio PSRR of FIG. 2.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

Claims (16)

A second current source having a first current source and a second current source, wherein one end of the first current source and one end of the second current source are commonly coupled and coupled to an internal power supply voltage corresponding to the first power supply voltage; A reference voltage generator including a current path; And And an amplifier having a differential amplifier structure receiving the first power voltage and negatively feeding back an internal power supply voltage corresponding to the first power voltage through the first current source and the second current source, respectively. The voltage at the other end of the first current source is input to the inverting input terminal, and the other end of the second current source is input to the non-inverting input terminal, and the first ground according to the virtual ground characteristics of the inverting input terminal and the non-inverting input terminal. The voltage between both ends of the current source and the voltage between both ends of the second current source are substantially the same so that the first current provided through the first current path and the second current provided through the second current path are substantially the same. Reference voltage generator circuit. The reference voltage generator circuit of claim 1, wherein the reference voltage generator circuit provides a voltage of the non-inverting input terminal as a reference voltage. The reference voltage generating circuit of claim 1, wherein the first current path further comprises a transistor having a voltage between the first current electrode and the control electrode which decreases with temperature. 4. The reference voltage generating circuit according to claim 3, wherein the first current path further comprises a circuit element for amplifying a voltage which increases with temperature between the first current source and the transistor with a predetermined resistance ratio. The method of claim 1, wherein the first current path is A first resistor element having one end coupled to the other end of the first current source; A second resistance element having one end coupled to the other end of the first resistance element; And And a first transistor having a first current electrode coupled to the other end of the second resistance element, a control electrode coupled to a second power supply voltage, and a second current electrode coupled to the second power supply voltage. Voltage generating circuit. The method of claim 5, wherein the second current path is A third resistance element having one end coupled to the other end of the second current source; And a second transistor having a first current electrode coupled to the other end of the third resistance element, a control electrode coupled to the second power supply voltage, and a second current electrode coupled to the second power supply voltage. Reference voltage generator circuit. The reference voltage generator circuit of claim 6, wherein the second resistor element and the third resistor element have the same resistance value. The reference voltage generator of claim 6, wherein the voltage between the first current electrode and the control electrode of the first transistor decreases with temperature. The method of claim 6, wherein the amplification unit A third transistor having a first current electrode coupled to the first power supply voltage; A fourth transistor having a first current electrode coupled to the first power voltage, a control electrode connected to a control electrode of the first transistor, and a second current electrode connected to the control electrode; A fifth transistor having a first current electrode coupled to a second current electrode of the third transistor and a control electrode coupled to the inverting input terminal; A sixth transistor having a first current electrode coupled to the first current electrode of the fifth transistor and a control electrode coupled to the non-inverting input terminal; A seventh transistor having a first current electrode coupled to a second current electrode of the fifth transistor, a control electrode coupled to the first current electrode, and a second current electrode coupled to the second power supply voltage; An eighth transistor having a first current electrode coupled to a second current electrode of the sixth transistor, a control electrode coupled to a control electrode of the seventh transistor, and a second current electrode coupled to the second power supply voltage; A first current electrode coupled to a second current electrode of the fourth transistor, a control electrode coupled to a first current electrode of the eighth transistor and connected to the first current electrode through a compensation resistor and a compensation capacitor, the second current electrode A ninth transistor having a second current electrode coupled with a power supply voltage; And A tenth transistor having a first current electrode coupled with a second current electrode of the third transistor, a control electrode coupled with a control electrode of the seventh transistor, and a second current electrode coupled with the second power voltage. A reference voltage generator circuit, characterized in that. 10. The method of claim 9, wherein the current flowing through the ninth transistor has a current value of k (k is a positive real number) times the first current provided to the first current path to maintain the virtual ground characteristic. A reference voltage generator circuit. 10. The reference voltage generator of claim 9, wherein the seventh transistor, the eighth transistor, and the ninth transistor are used to perform a two-stage amplification operation so as to maintain the virtual ground characteristics of the amplifier. i) a first current source coupled at one end to an internal power supply voltage, a first resistor coupled to the other end of the first current source, a second resistor coupled to the other end of the first resistor, and the second resistor A first current path having a first transistor having a first current electrode coupled to the other end of the second electrode, a control electrode coupled to a second power supply voltage, and a first transistor having a second current electrode coupled to the second power supply voltage; A second current source coupled to an internal power supply voltage, a third resistance element having one end coupled to the other end of the second current source, a first current electrode coupled with the other end of the third resistance element, and a control coupled with the second power supply voltage A reference voltage generator including a second current path having an electrode and a second transistor having a second current electrode coupled with the second power voltage; And And an amplifier having a differential amplifier structure receiving the first power voltage and negatively feeding back an internal power supply voltage corresponding to the first power voltage through the first current source and the second current source, respectively. The voltage at the other end of the first current source is input to the inverting input terminal, and the other end of the second current source is input to the non-inverting input terminal, and the first ground according to the virtual ground characteristics of the inverting input terminal and the non-inverting input terminal. The voltage between both ends of the current source and the voltage between both ends of the second current source are substantially the same so that the first current provided through the first current path and the second current provided through the second current path are substantially the same. Reference voltage generator circuit. The reference voltage generator circuit of claim 12, wherein the second resistor element and the third resistor element have the same resistance value. The method of claim 13, wherein the amplification unit A third transistor having a first current electrode coupled to the first power supply voltage; A fourth transistor having a first current electrode coupled to the first power voltage, a control electrode connected to a control electrode of the first transistor, and a second current electrode connected to the control electrode; A fifth transistor having a first current electrode coupled to a second current electrode of the third transistor and a control electrode coupled to the inverting input terminal; A sixth transistor having a first current electrode coupled to the first current electrode of the fifth transistor and a control electrode coupled to the non-inverting input terminal; A seventh transistor having a first current electrode coupled to a second current electrode of the fifth transistor, a control electrode coupled to the first current electrode, and a second current electrode coupled to the second power supply voltage; An eighth transistor having a first current electrode coupled to a second current electrode of the sixth transistor, a control electrode coupled to a control electrode of the seventh transistor, and a second current electrode coupled to the second power supply voltage; A first current electrode coupled to a second current electrode of the fourth transistor, a control electrode coupled to a first current electrode of the eighth transistor and connected to the first current electrode through a compensation resistor and a compensation capacitor, the second current electrode A ninth transistor having a second current electrode coupled with a power supply voltage; And A tenth transistor having a first current electrode coupled with a second current electrode of the third transistor, a control electrode coupled with a control electrode of the seventh transistor, and a second current electrode coupled with the second power voltage. A reference voltage generator circuit, characterized in that. 15. The method of claim 14, wherein the current flowing through the ninth transistor has a current value of k (k is a positive real number) times the first current provided to the first current path to maintain the virtual ground characteristic. A reference voltage generator circuit. 15. The reference voltage generator of claim 14, wherein the seventh transistor, the eighth transistor, and the ninth transistor are used to perform a two-stage amplification operation so as to maintain the virtual ground characteristics of the amplifier.