Power series current source generation circuit and system for use in an analog-to-digital converter

Abstract

The power series current source generation circuit applied to an analog-to-digital converter comprises a linear voltage-controlled current source and a power series current generation module; the linear voltage-controlled current source and the power series current generation module are electrically connected; the linear voltage-controlled current source is used for providing linear voltage-controlled current for the power series current generation module, and the power series current generation module is used for generating current proportional to the cube of a reference voltage. The power series current source generation circuit utilizes the exponential relationship between the collector current of an NPN type transistor and the base-emitter voltage; the power series current source generation circuit generates current proportional to the cube of the reference voltage; the current compensation circuit utilizes voltage bias to generate bias current, thereby solving the problem that the fixed voltage difference of the source follower changes with temperature.

Description

Technical Field

[0001] This invention belongs to the field of current source generation circuit technology, and specifically relates to a power-order current source generation circuit and system applied to analog-to-digital converters. Background Technology

[0002] With the increasing national demand and requirements for domestically produced military and aerospace chips, the localization of core technologies for analog-to-digital converter (ADC) chips used in the military industry, as one of the core circuits, is imperative. Since many chips in the military industry require positive and negative high-voltage inputs, from a performance perspective, high-voltage processes must be used to acquire the high-voltage input signals, which are then processed by the back-end ADC. However, due to the nonlinearity of the sampling capacitor, an input nonlinearity proportional to the cube of the reference voltage is generated, resulting in integral nonlinearity of the ADC. Changes in the closed-loop operational amplifier input current affect the front-end voltage divider resistor module. Summary of the Invention

[0003] The purpose of this invention is to provide a power-order current source generation circuit and system for analog-to-digital converters to solve the above-mentioned problems.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A power-order current source generation circuit for analog-to-digital converters includes a linear voltage-controlled current source and a power-order current generation module; the linear voltage-controlled current source and the power-order current generation module are electrically connected; the linear voltage-controlled current source is used to provide linear voltage-controlled current to the power-order current generation module, and the power-order current generation module is used to generate a current proportional to the cube of the reference voltage.

[0006] Furthermore, the linear voltage-controlled current source includes a first P-type MOSFET, a second P-type MOSFET, a third P-type MOSFET, a fourth P-type MOSFET, a fifth P-type MOSFET, a sixth P-type MOSFET, a seventh P-type MOSFET, a first N-type MOSFET, a second N-type MOSFET, a third N-type MOSFET, and a first resistor; the drain of the first P-type MOSFET is connected to the source of the second P-type MOSFET and the third P-type MOSFET; the drain of the second P-type MOSFET is connected to the drain and gate of the first N-type MOSFET and the drain of the second N-type MOSFET; the drain of the third P-type MOSFET is connected to the source of the second N-type MOSFET. The drain of the S-type transistor is connected to the gate of the third N-type MOSFET; the sources of the first and second N-type MOSFETs and one end of the first resistor are connected to ground (GND); the gate of the third P-type MOSFET is connected to one end of the first resistor and the source of the third N-type MOSFET; the drain of the third N-type MOSFET is connected to the drain and gate of the fifth P-type MOSFET and the gate of the seventh P-type MOSFET; the drain of the fifth P-type MOSFET is connected to the drain and gate of the fourth P-type MOSFET and the gate of the sixth P-type MOSFET; the drain of the sixth P-type MOSFET is connected to the source of the seventh P-type MOSFET.

[0007] Furthermore, the sources of the first, fourth, and sixth P-type MOSFETs are connected to the power supply voltage VDD.

[0008] Furthermore, the gate of the first P-type MOSFET is connected to the bias voltage VB; the drain of the seventh P-type MOSFET is connected to the output current IB.

[0009] Furthermore, the gate of the second P-type MOSFET is connected to the input voltage REF.

[0010] Furthermore, the power-order current generation module includes a first-type NPN transistor, a second-type NPN transistor, a third-type NPN transistor, a fourth-type NPN transistor, a fifth-type NPN transistor, a sixth-type NPN transistor, a first-type linear voltage-controlled current source, a second-type linear voltage-controlled current source, and an amplifier; the output terminal of the first-type linear voltage-controlled current source is connected to the collector and base of the second NPN transistor, the base of the first NPN transistor, and the positive input terminal of the amplifier; the output terminal of the second-type linear voltage-controlled current source is connected to the first NPN transistor... The collector of the transistor is connected to the negative input terminal of the amplifier; the emitter of the first NPN transistor is connected to the collector and base of the third NPN transistor; the emitter of the third NPN transistor is connected to the base of the fifth NPN transistor and the output terminal of the amplifier; the emitter of the second NPN transistor is connected to the collector and base of the fourth NPN transistor; the emitter of the fourth NPN transistor is connected to the collector and base of the sixth NPN transistor; the emitters of the sixth and fifth NPN transistors are connected to ground voltage GND.

[0011] Furthermore, the input terminal of the first type of linear voltage-controlled current source is connected to the voltage REF.

[0012] Furthermore, the power supply terminals of both the first-type linear voltage-controlled current source and the second-type linear voltage-controlled current source are connected to the power supply voltage VDD.

[0013] Furthermore, the collector of the fifth NPN transistor is connected to the output current ICQ5.

[0014] Furthermore, a power-series current source generation system applied to an analog-to-digital converter includes a current source module and a power-series current generation module; the linear voltage-controlled current source and the power-series current generation module are electrically connected; the current source module is used to provide linear voltage-controlled current to the power-series current generation module, and the power-series current generation module is used to generate a current proportional to the cube of the reference voltage.

[0015] Compared with the prior art, the present invention has the following technical effects:

[0016] The power-order current source generation circuit of this invention utilizes the exponential relationship between the collector current and the base-emitter voltage of an NPN transistor. This power-order current source generation circuit generates a current proportional to the cube of the reference voltage. The current compensation circuit uses voltage bias to generate bias current, solving the problem of the fixed voltage difference of the source follower changing with temperature. This current compensation circuit isolates the input signal through a P-type MOS source follower, solving the problem of the influence of the closed-loop operational amplifier input current change on the front-end voltage divider resistor module. The output stage circuit has the ability to absorb and provide current, solving the problem of excessive current caused by the compensation circuit. By compensating the base current, this circuit keeps the reference quiescent current constant, so that the reference output voltage is not affected by the analog-to-digital converter input signal, thus improving the performance of the analog-to-digital converter. Attached Figure Description

[0017] Figure 1 Linear voltage-controlled current source generation circuit;

[0018] Figure 2 Power series current generation circuit; Detailed Implementation

[0019] Please see Figure 1 and Figure 2 A power-series current source generation circuit and system for analog-to-digital converters, comprising a linear voltage-controlled current source and a power-series current generation circuit connected in sequence.

[0020] Linear voltage-controlled current source generation circuit: It consists of seven P-type MOSFETs, three N-type MOSFETs, and one resistor, and its characteristics are as follows:

[0021] As a further explanation of the above scheme, the linear voltage-controlled current source generating circuit includes a first P-type MOSFET, a second P-type MOSFET, a third P-type MOSFET, a fourth P-type MOSFET, a fifth P-type MOSFET, a sixth P-type MOSFET, a seventh P-type MOSFET, a first N-type MOSFET, a second N-type MOSFET, a third N-type MOSFET, and a first resistor.

[0022] The sources of the first, fourth, and sixth P-type MOSFETs are connected to the power supply voltage VDD.

[0023] The gate of the first P-type MOS transistor is connected to the bias voltage VB;

[0024] The drain of the first P-type MOS transistor is connected to the source of the second and third P-type MOS transistors;

[0025] The gate of the second P-type MOSFET is connected to the input voltage REF;

[0026] The drain of the second P-type MOS transistor is connected to the drain and gate of the first N-type MOS transistor and the drain of the second N-type MOS transistor.

[0027] The drain of the third P-type MOS transistor is connected to the drain of the second N-type MOS transistor and the gate of the third N-type MOS transistor.

[0028] The sources of the first N-type MOS transistor and the second N-type MOS transistor, as well as one end of the first resistor, are connected to ground voltage GND;

[0029] The gate of the third P-type MOS transistor is connected to one end of the first resistor and the source of the third N-type MOS transistor.

[0030] The drain of the third N-type MOS transistor is connected to the drain and gate of the fifth P-type MOS transistor and the gate of the seventh P-type MOS transistor.

[0031] The drain of the fifth P-type MOS transistor is connected to the drain and gate of the fourth P-type MOS transistor and the gate of the sixth P-type MOS transistor.

[0032] The drain of the sixth P-type MOS transistor is connected to the source of the seventh P-type MOS transistor.

[0033] The drain of the seventh P-type MOSFET is connected to the output current IB;

[0034] Power-series current generation circuit: It consists of six NPN transistors, two linear voltage-controlled current sources, and one amplifier, and its characteristics are as follows:

[0035] As a further explanation of the above scheme, the power series current generation circuit includes a first type NPN transistor, a second type NPN transistor, a third type NPN transistor, a fourth type NPN transistor, a fifth type NPN transistor, a sixth type NPN transistor, a first type linear voltage-controlled current source, a second type linear voltage-controlled current source, and an amplifier.

[0036] The circuit reference for the linear voltage-controlled current source (VCCS) is as follows. Figure 1 );

[0037] The input terminal of the first type of linear voltage-controlled current source is connected to the voltage REF;

[0038] The power supply terminal of the first type of linear voltage-controlled current source and the second type of linear voltage-controlled current source are connected to the power supply voltage VDD;

[0039] The output terminal of the first type of linear voltage-controlled current source is connected to the collector and base of the second NPN transistor, the base of the first NPN transistor, and the positive input terminal of the amplifier.

[0040] The output terminal of the second type linear voltage-controlled current source is connected to the collector of the first NPN transistor and the negative input terminal of the amplifier;

[0041] The emitter of the first NPN transistor is connected to the collector and base of the third NPN transistor;

[0042] The emitter of the third NPN transistor is connected to the base of the fifth NPN transistor and the output terminal of the amplifier;

[0043] The emitter of the second NPN transistor is connected to the collector and base of the fourth NPN transistor;

[0044] The emitter of the fourth NPN transistor is connected to the collector and base of the sixth NPN transistor;

[0045] The emitters of the sixth NPN transistor and the fifth NPN transistor are connected to ground voltage GND;

[0046] The collector of the fifth NPN transistor is connected to the output current ICQ5.

[0047] Example:

[0048] A power-order current source generation circuit for analog-to-digital converters includes a linear voltage-controlled current source and a power-order current generation module; the linear voltage-controlled current source and the power-order current generation module are electrically connected; the linear voltage-controlled current source is used to provide linear voltage-controlled current to the power-order current generation module, and the power-order current generation module is used to generate a current proportional to the cube of the reference voltage.

[0049] The power-series current generation module includes a first-type NPN transistor, a second-type NPN transistor, a third-type NPN transistor, a fourth-type NPN transistor, a fifth-type NPN transistor, a sixth-type NPN transistor, a first-type linear voltage-controlled current source, a second-type linear voltage-controlled current source, and an amplifier. The output terminal of the first-type linear voltage-controlled current source is connected to the collector and base of the second NPN transistor, the base of the first NPN transistor, and the positive input terminal of the amplifier. The output terminal of the second-type linear voltage-controlled current source is connected to the collector and base of the first NPN transistor. The collector of the first NPN transistor is connected to the negative input terminal of the amplifier; the emitter of the first NPN transistor is connected to the collector and base of the third NPN transistor; the emitter of the third NPN transistor is connected to the base of the fifth NPN transistor and the output terminal of the amplifier; the emitter of the second NPN transistor is connected to the collector and base of the fourth NPN transistor; the emitter of the fourth NPN transistor is connected to the collector and base of the sixth NPN transistor; the emitters of the sixth and fifth NPN transistors are connected to ground (GND). The input terminal of the first-type linear voltage-controlled current source is connected to the voltage REF.

[0050] The power supply terminals of the first and second type linear voltage-controlled current sources are connected to the power supply voltage VDD. The collector of the fifth NPN transistor is connected to the output current ICQ5.

[0051] This power-series current source generating circuit utilizes the exponential relationship between the collector current and the base-emitter voltage of an NPN transistor; the power-series current source generating circuit generates a current that is proportional to the cube of the reference voltage.

[0052] In another embodiment of the present invention, a power-series current source generation system for analog-to-digital converters is provided, which can be used to implement the above-described power-series current source generation method for analog-to-digital converters. Specifically, the power-series current source generation system for analog-to-digital converters includes:

[0053] The current source module and the power series current generation module are electrically connected; the linear voltage-controlled current source and the power series current generation module are used to provide linear voltage-controlled current to the power series current generation module, and the power series current generation module is used to generate a current proportional to the cube of the reference voltage.

[0054] The module division in this embodiment of the invention is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of the invention can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A power-series current source generation circuit applied to an analog-to-digital converter, characterized in that, It includes a linear voltage-controlled current source and a power-series current generation module; the linear voltage-controlled current source and the power-series current generation module are electrically connected; the linear voltage-controlled current source is used to provide linear voltage-controlled current to the power-series current generation module, and the power-series current generation module is used to generate a current proportional to the cube of the reference voltage; The linear voltage-controlled current source includes a first P-type MOSFET, a second P-type MOSFET, a third P-type MOSFET, a fourth P-type MOSFET, a fifth P-type MOSFET, a sixth P-type MOSFET, a seventh P-type MOSFET, a first N-type MOSFET, a second N-type MOSFET, a third N-type MOSFET, and a first resistor; the drain of the first P-type MOSFET is connected to the source of the second P-type MOSFET and the third P-type MOSFET; the drain of the second P-type MOSFET is connected to the drain and gate of the first N-type MOSFET and the drain of the second N-type MOSFET; the drain of the third P-type MOSFET is connected to the source of the second N-type MOSFET. The drain of the first N-type MOSFET is connected to the gate of the second N-type MOSFET; the source of the first N-type MOSFET and the second N-type MOSFET, as well as one end of the first resistor, are connected to ground (GND); the gate of the third P-type MOSFET is connected to one end of the first resistor and the source of the third N-type MOSFET; the drain of the third N-type MOSFET is connected to the drain and gate of the fifth P-type MOSFET and the gate of the seventh P-type MOSFET; the drain of the fifth P-type MOSFET is connected to the drain and gate of the fourth P-type MOSFET and the gate of the sixth P-type MOSFET; the drain of the sixth P-type MOSFET is connected to the source of the seventh P-type MOSFET. The gate of the second P-type MOSFET is connected to the input voltage REF.

2. The power-series current source generation circuit for analog-to-digital converters according to claim 1, characterized in that, The sources of the first, fourth, and sixth P-type MOSFETs are connected to the power supply voltage VDD.

3. The power-series current source generation circuit for analog-to-digital converters according to claim 1, characterized in that, The gate of the first P-type MOSFET is connected to the bias voltage VB; the drain of the seventh P-type MOSFET is connected to the output current IB.

4. The power-series current source generation circuit for analog-to-digital converters according to claim 1, characterized in that, The power-series current generation module includes a first-type NPN transistor, a second-type NPN transistor, a third-type NPN transistor, a fourth-type NPN transistor, a fifth-type NPN transistor, a sixth-type NPN transistor, a first-type linear voltage-controlled current source, a second-type linear voltage-controlled current source, and an amplifier. The output terminal of the first-type linear voltage-controlled current source is connected to the collector and base of the second NPN transistor, the base of the first NPN transistor, and the positive input terminal of the amplifier. The output terminal of the second-type linear voltage-controlled current source is connected to the collector and base of the first NPN transistor. The collector of the first NPN transistor is connected to the negative input terminal of the amplifier; the emitter of the first NPN transistor is connected to the collector and base of the third NPN transistor; the emitter of the third NPN transistor is connected to the base of the fifth NPN transistor and the output terminal of the amplifier; the emitter of the second NPN transistor is connected to the collector and base of the fourth NPN transistor; the emitter of the fourth NPN transistor is connected to the collector and base of the sixth NPN transistor; the emitters of the sixth and fifth NPN transistors are connected to ground voltage GND.

5. The power-series current source generation circuit for analog-to-digital converters according to claim 4, characterized in that, The input terminal of the first type of linear voltage-controlled current source is connected to the voltage REF.

6. The power-series current source generation circuit for an analog-to-digital converter according to claim 4, characterized in that, The power supply terminals of the first-type linear voltage-controlled current source and the second-type linear voltage-controlled current source are connected to the power supply voltage VDD.

7. The power-series current source generation circuit for analog-to-digital converters according to claim 4, characterized in that, The collector of the fifth NPN transistor is connected to the output current ICQ5.

8. A power-series current source generation system applied to an analog-to-digital converter, characterized in that, It includes a current source module and a power series current generation module; the linear voltage-controlled current source and the power series current generation module are electrically connected; the current source module is used to provide linear voltage-controlled current to the power series current generation module, and the power series current generation module is used to generate a current proportional to the cube of the reference voltage.

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