TW201539171A - Temperature-independent integrated voltage and current source - Google Patents

Abstract

The present invention is directed to a temperature-independent integrated voltage and current source, in which a voltage source branch includes series-connected at least one metal-oxide-semiconductor (MOS) transistor and a bipolar junction transistor (BJT), wherein the MOS transistor is folded with a positive-temperature-coefficient current source such that a current thereof is mirrored into the voltage source branch. A current source branch includes series-connected at least one MOS transistor and parallel-connected transistor and BJT, wherein the MOS transistor is folded with the positive-temperature-coefficient current source such that a current thereof is mirrored into the current source branch.

Description

Temperature uncorrelated integrated voltage source and current source

The present invention relates to an integrated power supply, and more particularly to an integrated voltage source and current source that is temperature independent.

A bandgap voltage source is a commonly used voltage source whose reference voltage is not affected by temperature changes, that is, its temperature coefficient is zero. Although the current value has a simple relationship with the voltage value (ie, current = voltage / resistance), the temperature coefficient of almost all resistors will not be zero, therefore, it cannot be directly from the temperature uncorrelated voltage source (for example, Gap voltage source) to obtain a temperature-independent current source.

Since the conventional method of generating the reference voltage and the reference current is different, it is difficult to integrate the two. Therefore, if it is necessary to provide both a voltage source and a current source, the voltage source circuit and the current source circuit are generally designed to provide a reference voltage and a reference current, respectively. However, such a circuit design can occupy a considerable circuit area, resulting in wasted area and power consumption.

Therefore, it is urgent to propose a temperature-independent integrated voltage source and current source to improve the shortcomings of conventional voltage sources and current sources.

In view of the above, one of the objects of the embodiments of the present invention is to provide a temperature-independent integrated voltage source and current source that share a main circuit to provide a temperature-independent reference voltage and a reference current, thereby saving a large amount of circuit area. And power consumption.

According to an embodiment of the invention, the temperature uncorrelated integrated voltage source and current source comprise a positive temperature coefficient current source, a voltage source circuit branch and a current source circuit branch. The voltage source circuit branch includes at least one metal oxide semiconductor transistor and a bipolar junction transistor connected in series, wherein the metal oxide semiconductor transistor is folded and coupled to the positive temperature coefficient current source such that the current flowing through the positive temperature coefficient current source The current mirror is incident on the voltage source circuit branch. The current source circuit branch includes at least one metal oxide semiconductor transistor connected in series and a parallel connected resistor and a bipolar junction transistor, wherein the metal oxide semiconductor transistor is folded and coupled to the positive temperature coefficient current source, so that the flow The current of the positive temperature coefficient current source is mirrored to the current source circuit branch.

The first figure shows a circuit diagram of a temperature-independent integrated voltage source and current source (hereinafter referred to as an integrated power source) according to an embodiment of the present invention. The second A diagram shows the voltage source portion of the integrated power supply of the first figure, and the second B diagram shows the current source portion of the integrated power supply of the first figure.

As shown in the first figure, the voltage source (second A picture) of the present embodiment shares a positive temperature coefficient current source 11 with the current source (second B picture), as shown in the second C. Therefore, the integrated power supply of the embodiment can save a large amount of circuit area and power consumption. The positive temperature coefficient current source 11 shown in the second C diagram is merely an example, and may be replaced with another current source having a positive temperature coefficient.

In the present embodiment, as shown in the second C diagram, the positive temperature coefficient current source 11 includes a first circuit branch and a second circuit branch, which are connected in parallel. In detail, the first circuit branch sequentially connects at least one P-type metal oxide semiconductor (MOS) transistor P1, P2, and at least one N-type metal oxide semiconductor (MOS) transistor N1 from the power source to the ground. N2, resistor R1 and a bipolar junction transistor (for example, a PNP type transistor whose ground level is grounded) B1. The P-type metal oxide semiconductor (MOS) transistors P1 and P2 are diode-coupled versions, that is, the gate and the drain are electrically coupled to each other. The second circuit branch sequentially connects at least one P-type metal oxide semiconductor (MOS) transistor P3, P4, at least one N-type metal oxide semiconductor (MOS) transistor N3, N4 and the bipolar connection from the power source to the ground. A surface transistor (for example, a PNP type transistor whose ground level is grounded) B2. The N-type metal oxide semiconductor (MOS) transistors N3 and N4 are diode-coupled versions, that is, the gate and the drain are electrically coupled to each other. In this embodiment, the area of the bipolar junction transistor B1 of the first circuit branch is a multiple of the area of the bipolar junction transistor B2 of the second circuit branch (the value of which is greater than one). The metal oxide semiconductor (MOS) transistors P1, P2, N1, and N2 of the first circuit branch are respectively coupled with the metal oxide semiconductor (MOS) transistors P3, P4, N3, and N4 of the second circuit branch. Connected, that is, the corresponding gates are coupled to each other. According to the positive temperature coefficient current source 11 described above, the current flowing through the first circuit branch or the second circuit branch rises as the temperature rises, that is, has a positive temperature coefficient.

As shown in FIG. 2A, the (non-temperature dependent) voltage source of the integrated power supply includes, in addition to the positive temperature coefficient current source 11, a voltage source circuit branch 12, which is connected in series with at least one metal from the power source to the ground. Oxide semiconductor (MOS) transistors (for example, P-type MOS transistors) P5, P6, resistor R2, and bipolar junction transistors (for example, PNP-type transistors whose base is grounded) B3. The metal oxide semiconductor (MOS) transistors P5 and P6 are folded and coupled to the positive temperature coefficient current source 11, for example, a P-type metal oxide semiconductor (MOS) electrically coupling the gate to the positive temperature coefficient current source 11. The gate of the transistor (P1, P2 or P3, P4) thus forms a current mirror circuit such that current flowing through the positive temperature coefficient current source 11 (the first circuit branch or the second circuit branch) is mirrored Voltage source circuit branch 12.

According to the voltage source described above (second A diagram), the mirror current flowing through the voltage source circuit branch 12 has a positive temperature coefficient, and the bipolar junction transistor B3 has a negative temperature coefficient. By adjusting the values of resistors R1 and R2, a non-temperature dependent (reference) voltage output Vref can be provided at the junction between metal oxide semiconductor (MOS) transistor P6 and resistor R2. Thereby, the voltage source shown in FIG. 2A forms a bandgap voltage source which is unaffected by temperature changes.

As shown in FIG. 2B, the (non-temperature dependent) current source of the integrated power supply includes, in addition to the positive temperature coefficient current source 11, a current source circuit branch 13, which has at least one two connected in series from the power source to the ground. Metal-oxide-semiconductor (MOS) transistors P7, P8, at least one metal-oxide-semiconductor (MOS) transistor (eg, N-type) of a polar body coupling type (ie, a gate and a drain are electrically coupled to each other) MOS transistor) N5, N6, and the parallel connected resistor R3 and a bipolar junction transistor (for example, a PNP type transistor whose base is grounded) B4. Wherein, the metal oxide semiconductor (MOS) transistors N5, N6 are folded and coupled to the positive temperature coefficient current source 11, for example, an N-type metal oxide semiconductor (MOS) transistor that couples the gate to the positive temperature coefficient current source 11. a gate of (N1, N2 or N3, N4) thus forming a current mirror circuit such that current flowing through the positive temperature coefficient current source 11 (the first circuit branch or the second circuit branch) is mirrored to the current source Circuit branch 13. In the present embodiment, the area of the bipolar junction transistor B4 of the current source circuit branch 13 is the same as the area of the bipolar junction transistor B2 of the second circuit branch.

According to the above current source (second B diagram), the mirror current flowing through the current source circuit branch 13 has a positive temperature coefficient, and the bipolar junction transistor B4 has a negative temperature coefficient. By adjusting the values of resistors R1 and R3, a non-temperature dependent (reference) current can be provided, for example, an additional current mirror circuit (not shown) can be used to mirror the non-temperature dependent current.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention; all other equivalent changes or modifications which are not departing from the spirit of the invention should be included in the following Within the scope of the patent application.

11‧‧‧ Positive temperature coefficient current source
12‧‧‧Voltage source circuit branch
13‧‧‧ Current source circuit branch
P1~P8‧‧‧P type metal oxide semiconductor transistor
N1~N6‧‧‧N type metal oxide semiconductor transistor
R1~R3‧‧‧Resistors
B1~B4‧‧‧Bipolar junction transistor
Vref‧‧‧ voltage output

The first figure shows a circuit diagram of a temperature-independent integrated voltage source and current source in accordance with an embodiment of the present invention. Figure 2A shows the voltage source portion of the integrated power supply of the first figure. The second B diagram shows the current source portion of the integrated power supply of the first figure. The second C diagram shows the positive temperature coefficient current source of the integrated power supply of the first figure.

11‧‧‧ Positive temperature coefficient current source

12‧‧‧Voltage source circuit branch

13‧‧‧ Current source circuit branch

P1~P8‧‧‧P type metal oxide semiconductor transistor

N1~N6‧‧‧N type metal oxide semiconductor transistor

R1~R3‧‧‧Resistors

B1~B4‧‧‧Bipolar junction transistor

Vref‧‧‧ voltage output

Claims (13)

A temperature-independent integrated voltage source and current source comprising: a positive temperature coefficient current source; a voltage source circuit branch comprising at least one metal oxide semiconductor transistor and a bipolar junction transistor in series, wherein the metal An oxide semiconductor transistor is folded coupled to the positive temperature coefficient current source such that a current flowing through the positive temperature coefficient current source is mirrored to the voltage source circuit branch; and a current source circuit branch includes at least one metal connected in series An oxide semiconductor transistor and a parallel resistor and a bipolar junction transistor, wherein the metal oxide semiconductor transistor is folded coupled to the positive temperature coefficient current source such that a current mirror flows through the positive temperature coefficient current source Shooted to the current source circuit branch. The temperature-independent integrated voltage source and current source according to claim 1, wherein the gate of the metal oxide semiconductor transistor branched from the voltage source circuit is electrically coupled to the metal oxide of the positive temperature coefficient current source The gate of the semiconductor transistor to form a current mirror circuit. The temperature-independent integrated voltage source and current source according to the first aspect of the patent application, wherein the voltage source circuit branch further comprises a resistor electrically coupled to the metal oxide semiconductor transistor and the bipolar junction Between crystals. The temperature-independent integrated voltage source and current source according to claim 3, wherein the metal oxide semiconductor transistor branched by the voltage source circuit comprises a P-type metal oxide semiconductor transistor, and the bipolar junction is electrically The crystal contains a PNP type bipolar junction transistor. The temperature non-correlated integrated voltage source and current source according to claim 4, wherein the voltage source circuit branches from the power source to the ground in sequence with a P-type metal oxide semiconductor transistor, the resistor, and a resistor The PNP type bipolar junction transistor has its base level grounded. According to the temperature range non-correlated integrated voltage source and current source according to claim 1, wherein the gate of the metal oxide semiconductor transistor branched from the current source circuit is electrically coupled to the metal oxidation of the positive temperature coefficient current source The gate of the semiconductor transistor to form a current mirror circuit. The temperature-independent integrated voltage source and current source according to claim 1 of the patent application scope, wherein the current source circuit branches are further connected in series with at least one diode-coupled type of metal oxide semiconductor transistor. The temperature-independent integrated voltage source and current source according to claim 7 of the patent application scope, wherein the metal oxide semiconductor transistor branched by the current source circuit comprises an N-type metal oxide semiconductor transistor, the diode coupling type The metal oxide semiconductor transistor of the state comprises a P-type metal oxide semiconductor transistor, and the bipolar junction transistor comprises a PNP type bipolar junction transistor. The temperature-independent integrated voltage source and current source according to claim 8 of the patent application scope, wherein the current source circuit branches from the power source to the ground in sequence with two diode-coupled P-type metal oxides A semiconductor transistor, a two-N metal oxide semiconductor transistor, and a parallel-connected resistor and a PNP-type bipolar junction transistor are grounded at the base level. The temperature non-correlated integrated voltage source and current source according to claim 1 of the patent application scope, wherein the positive temperature coefficient current source comprises: a first circuit branch, wherein at least one P-type metal oxide is serially connected in series from the power source to the ground a semiconductor transistor, at least one N-type metal oxide semiconductor transistor, a resistor and a bipolar junction transistor; and a second circuit branch having at least one P-type metal oxide semiconductor serially connected from the power source to the ground A transistor, at least one N-type metal oxide semiconductor transistor and a bipolar junction transistor. The temperature-independent integrated voltage source and current source according to claim 10, wherein the bipolar junction transistor of the first circuit branch comprises a PNP type bipolar junction transistor, and the second circuit branch The bipolar junction transistor comprises a PNP type bipolar junction transistor. The temperature-independent integrated voltage source and current source according to claim 11 of the patent application scope, wherein the P-type metal oxide semiconductor crystal system of the first circuit branch is a diode coupling type, and the bipolar junction The base of the transistor is grounded; wherein the N-type metal oxide semiconductor crystal system of the second circuit branch is a diode coupling type, and the base of the bipolar junction transistor is grounded. The temperature-independent integrated voltage source and current source according to claim 10, wherein the area of the bipolar junction transistor of the first circuit branch is a bipolar junction transistor of the second circuit branch, and The current source circuit branches a multiple of the area of the bipolar junction transistor, the value of which is greater than one.