Control system for high-voltage common-mode loop

Abstract

The invention provides a control system for a high-voltage common-mode loop, and the system comprises a low-voltage amplification module which is provided with an output end, a virtual short adjustment end, and an input end for inputting a low-voltage adjustment voltage; the high-voltage amplification module is coupled with the output end of the low-voltage amplification module and is provided with a first differential output end and a second differential output end; and the adjusting module is coupled with the virtual short adjusting end and is provided with a first common-mode output end and a second common-mode output end, the first common-mode output end is coupled with the first differential output end, and the second common-mode output end is coupled with the second differential output end, so that common-mode voltage formed by the first differential output end and the second differential output end is associated with the low-voltage adjusting voltage. According to the circuit, high-voltage control can be converted into low-voltage control, so that a worker can conveniently control a common-mode level of a high-voltage chip; the loop common-mode level is not a fixed value and can be freely controlled, so that personnel can conveniently adjust according to actual requirements.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor design, and in particular to a high-voltage common-mode loop control system. Background Art

[0002] In traditional common-mode feedback loop control, the common-mode voltage is often a fixed value, which has limitations on the adjustment of the entire loop. Secondly, there are also process differences when adjusting the common-mode voltage of high- and low-voltage packaged chips. The withstand voltage values ​​of high and low voltage devices are different. The withstand voltage of low-voltage chips is about 3.3V, and the withstand voltage of high-voltage chips is more than 100V, which makes it inconvenient to adjust the common-mode voltage of high- and low-voltage packaged chips. Summary of the invention

[0003] The present application provides a high-voltage common-mode loop control system, which facilitates adjustment of the common-mode voltage of high- and low-voltage packaged chips.

[0004] A high voltage common mode loop control system of the present application;

[0005] A high voltage common mode loop control system, comprising:

[0006] A low voltage amplification module, having an output terminal, a virtual short regulating terminal and an input terminal for inputting a low voltage regulating voltage;

[0007] The high voltage amplification module is coupled to the output end of the low voltage amplification module and has a first differential output end and a second differential output end;

[0008] The regulation module is coupled to the virtual short regulation terminal and has a first common mode output terminal and a second common mode output terminal. The first common mode output terminal is coupled to the first differential output terminal, and the second common mode output terminal is coupled to the second differential output terminal so that the common mode voltage formed by the first differential output terminal and the second differential output terminal is associated with the low voltage regulation voltage.

[0009] Preferably, the regulation module includes an operational amplifier A1 and two voltage control units, the voltage control unit includes a resistor R1 and a resistor R3, the resistor R1 and the resistor R3 are connected in series, the electrical connection point between the resistor R1 and the resistor R3 is coupled to the input end of the operational amplifier A1, the other end of the resistor R3 is coupled to the output end of the operational amplifier A1, and the other ends of the two resistors R1 are respectively a first common-mode output end and a second common-mode output end.

[0010] Preferably, a resistor R2 is connected in series between the electrical connection point between the resistor R1 and the resistor R3 and the virtual short adjustment end.

[0011] Preferably, the high-voltage amplification module includes a first low-voltage control unit, a second low-voltage control unit and a high-voltage amplification unit. The first low-voltage control unit and the second low-voltage control unit are both coupled to the output end of the low-voltage amplification module. The first low-voltage control unit is coupled between an input end of the high-voltage amplification unit and a voltage source VIN respectively to control the on-off electrical connection between the high-voltage amplification unit and the voltage source VIN. The second low-voltage control unit is coupled between another input end of the high-voltage amplification unit and a voltage source VIP respectively to control the on-off electrical connection between the high-voltage amplification unit and the voltage source VIP. The first differential output end and the second differential output end are located on the high-voltage amplification unit.

[0012] Preferably, the high-voltage amplification unit is a differential operational amplifier A3.

[0013] Preferably, the first low-voltage control unit includes a low-voltage operational amplifier A4, a resistor R4 and a field effect transistor Q1, the output end of the low-voltage amplification module is coupled to the resistor R4, the other end of the resistor R4 is coupled to the input end of the low-voltage operational amplifier A4, the other input end of the low-voltage operational amplifier A4 is connected to the voltage VRFEF, the output end of the low-voltage operational amplifier A4 is coupled to the gate of the field effect transistor Q1, the drain of the field effect transistor Q1 is coupled to the differential operational amplifier A3, and the source of the field effect transistor Q1 is coupled to the voltage source VIN.

[0014] Preferably, a resistor R6 is connected in series between the source of the field effect transistor Q1 and the voltage source VIN.

[0015] Preferably, the second low-voltage control unit includes a low-voltage operational amplifier A5, a resistor R5 and a field effect transistor Q2, the output end of the low-voltage amplifier module is coupled to the resistor R5, the other end of the resistor R5 is coupled to the input end of the low-voltage operational amplifier A5, the other input end of the low-voltage operational amplifier A5 is connected to the voltage VRFEF, the output end of the low-voltage operational amplifier A5 is coupled to the gate of the field effect transistor Q2, the source of the field effect transistor Q2 is coupled to the voltage source VIP, and the drain of the field effect transistor Q2 is coupled to the differential operational amplifier A3.

[0016] Preferably, a resistor R7 is connected in series between the source of the field effect transistor Q2 and the voltage source VIP.

[0017] In a third aspect of the present application, an electronic device is provided.

[0018] In summary, this application includes the following beneficial technical effects:

[0019] 1. The circuit configuration of this application can convert high voltage control into low voltage control, thereby facilitating personnel to control the common mode level of the high voltage chip;

[0020] 2. The loop common mode level of this application is not a fixed value and can be freely controlled, which is convenient for personnel to adjust according to actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of a circuit structure for a high-voltage common-mode loop control system according to an embodiment of the present application.

[0022] Explanation of the accompanying drawings: 1. low-voltage amplifying module; 2. high-voltage amplifying module; 21. first low-voltage control unit; 22. second low-voltage control unit; 23. high-voltage amplifying unit; 3. regulating module; 31. voltage regulating unit. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments.

[0024] In the description of the embodiments of the present application, words such as "illustrative", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "illustrative", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "illustrative", "for example" or "for example" is intended to present related concepts in a concrete way.

[0025] In the description of the embodiments of the present application, the term "and / or" is only a kind of association relationship describing the associated objects, indicating that there may be three kinds of relationships, for example, A and / or B, which can represent: A exists alone, B exists alone, and A and B exist at the same time. In addition, unless otherwise specified, the meaning of the term "multiple" refers to two or more. For example, multiple systems refer to two or more systems, and multiple screen terminals refer to two or more screen terminals. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the indicated technical features. Thus, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. The terms "include", "comprise", "have" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0026] Scenario: In traditional common-mode feedback loop control, the common-mode voltage is often a fixed value, and there are limitations on the adjustment of the entire loop. Secondly, when adjusting the common-mode voltage of high- and low-voltage packaged chips, there will also be process differences, and different voltage domains and other issues make the design difficult. Therefore, the applicant designed this application to be able to use a low-voltage chip to control the common-mode voltage of a high-voltage chip.

[0027] Reference Figure 1 , a high voltage common mode loop control system, comprising a low voltage amplification module 1, a high voltage amplification module 2 and a regulation module 3;

[0028] The low voltage amplification module 1 is used for inputting a low voltage regulation voltage, and has an output terminal, an input terminal for inputting the low voltage regulation voltage, and a virtual short regulation terminal; the low voltage amplification module 1 includes an operational amplifier A2, two input terminals of the operational amplifier A2 are in a virtual short state, one input terminal inputs a voltage VSET, and the virtual short regulation terminal is another input terminal of the operational amplifier A2, and its voltage is VCOM; the voltage value of VCOM is equal to the voltage value of the voltage VSET;

[0029] The regulation module 3 is coupled to the virtual short regulation end. The regulation module 3 includes an operational amplifier A1 and two voltage regulation units 31. The voltage regulation unit 31 includes a resistor R1 and a resistor R3. The resistor R1 is connected in series with the resistor R3. The electrical connection point between the resistor R1 and the resistor R3 is coupled to the input end of the operational amplifier A1. The other end of the resistor R3 is coupled to the output end of the operational amplifier A1. The operational amplifier A1 is provided with two output ends and two input ends. The two ends of each voltage regulation unit 31 are respectively connected to an output end and an input end of the operational amplifier A1. The other ends of the two resistors R1 are respectively a first common-mode output end and a second common-mode output end; wherein, the common-mode voltage output by the two differential output ends of the operational amplifier A1 is 1.5V. A resistor R2 is connected in series between the electrical connection point between the resistor R1 and the resistor R3 and the virtual short regulation end; two resistors R2 are also provided corresponding to the voltage regulation unit 31;

[0030] The high-voltage amplifier module 2 is an integrated module of a differential operational amplifier. The high-voltage amplifier module 2 has a first differential output terminal and a second differential output terminal. The first common-mode output terminal is coupled to the first differential output terminal, and the second common-mode output terminal is coupled to the second differential output terminal. The common-mode voltage formed by the first differential output terminal and the second differential output terminal is associated with the low-voltage regulation voltage.

[0031] Specifically: operational amplifier A1 is a fully differential operational amplifier, the output common mode voltage of operational amplifier A1 is 1.5V, the voltage of the first differential output terminal is VOP, and the voltage of the second input terminal is VON; using Kirchhoff's current principle: the sum of the currents flowing into any node in the circuit is equal to the sum of the currents flowing out of the node, the following formula can be obtained:

[0032] (1)

[0033] (2)

[0034] Adding formula (1) and formula (2) yields:

[0035] (3)

[0036] Simplifying, we get:

[0037] (4)

[0038] in, is the common mode voltage of the circuit. In actual use, the output voltage of VOP and VON is as high as 100 volts. Here, the voltage reduction can be achieved by controlling the ratio of R1 / R3. By using the virtual short characteristic of operational amplifier A2, the voltage of VSET can be freely set to control the voltage of VCOM.

[0039] It should be noted that, generally speaking, the input end of a CMOS operational amplifier is in a high impedance state. In order to prevent the impedance at the operational amplifier A2 from being insufficiently high, the resistor R2 is added to further increase the impedance of the node.

[0040] Furthermore, the high-voltage amplification module 2 includes a first low-voltage control unit 21, a second low-voltage control unit 22 and a high-voltage amplification unit 23. The first low-voltage control unit 21 and the second low-voltage control unit 22 are both coupled to the output end of the low-voltage amplification module 1. The first low-voltage control unit 21 is coupled to an input end of the high-voltage amplification unit 23 and is respectively connected to the voltage source VIN to control the electrical connection between the high-voltage amplification unit 23 and the voltage source VIN. The second low-voltage control unit 22 is coupled to another input end of the high-voltage amplification unit 23 and is respectively connected to the voltage source VIP to control the electrical connection between the high-voltage amplification unit 23 and the voltage source VIP.

[0041] The high-voltage amplifier unit 23 is a differential operational amplifier A3, and the first differential output terminal and the second differential output terminal are two differential output pins on the differential operational amplifier A3; the first low-voltage control unit 21 includes a low-voltage operational amplifier A4, a resistor R4 and a field effect transistor Q1, the output terminal of the low-voltage amplifier module 1 is coupled to the resistor R4, the other end of the resistor R4 is coupled to the input terminal of the low-voltage operational amplifier A4, the other input terminal of the low-voltage operational amplifier A4 is connected to the voltage VRFEF, the output terminal of the low-voltage operational amplifier A4 is coupled to the gate of the field effect transistor Q1, the drain of the field effect transistor Q1 is coupled to the differential operational amplifier A3, the source of the field effect transistor Q1 is coupled to the voltage source VIN, and a resistor R6 is connected in series between the source of the field effect transistor Q1 and the voltage source VIN.

[0042] The second low-voltage control unit 22 includes a low-voltage operational amplifier A5, a resistor R5 and a field effect transistor Q2. The output end of the low-voltage amplifier module 1 is coupled to the resistor R5, the other end of the resistor R5 is coupled to the input end of the low-voltage operational amplifier A5, the other input end of the low-voltage operational amplifier A5 is connected to the voltage VRFEF, the output end of the low-voltage operational amplifier A5 is coupled to the gate of the field effect transistor Q2, the source of the field effect transistor Q2 is coupled to the voltage source VIP, the drain of the field effect transistor Q2 is coupled to the differential operational amplifier A3, and a resistor R7 is connected in series between the source of the field effect transistor Q2 and the voltage source VIP.

[0043] The low voltage operational amplifier A4 and the low voltage operational amplifier A5 also have the virtual short characteristic. The reference voltage VRFEF is 1.5V, so the node voltage of the other input pin voltage V2 of the low voltage operational amplifier A4 and the voltage value of the other input pin voltage V3 of the low voltage operational amplifier A5 are both 1.5V.

[0044] In actual operation, there is a voltage difference between the output voltage V1 of the operational amplifier A2 and the pin voltage V2 of the low-voltage operational amplifier A4, which forms a current. This current and the input current The high voltage amplifier unit 23 is amplified by the differential operational amplifier A3. Similarly, the function of the low voltage operational amplifier A5 is the same as that of the low voltage operational amplifier A4. The current is fixed and will not affect the common mode voltage. The current will adjust the common-mode voltage in real time to form a closed loop.

[0045] The above is only an exemplary embodiment of the present disclosure, and the scope of the present disclosure cannot be limited thereto. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure here, those skilled in the art will easily think of other embodiments of the present disclosure. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the technical field not recorded in the present disclosure. The description and examples are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

Claims

1. A high voltage common mode loop control system, characterized in that: include: A low voltage amplification module (1) has an output terminal, a virtual short regulating terminal and an input terminal for inputting a low voltage regulating voltage; The high voltage amplification module (2) is coupled to the output end of the low voltage amplification module (1), and has a first differential output end and a second differential output end; The regulating module (3) is coupled to the virtual short regulating terminal and has a first common mode output terminal and a second common mode output terminal, wherein the first common mode output terminal is coupled to the first differential output terminal, and the second common mode output terminal is coupled to the second differential output terminal so that a common mode voltage formed by the first differential output terminal and the second differential output terminal is associated with a low voltage regulating voltage.

2. A high voltage common mode loop control system according to claim 1, characterized in that: The regulating module (3) comprises an operational amplifier A1 and two voltage regulating units (31), the voltage regulating unit (31) comprises a resistor R1 and a resistor R3, the resistor R1 and the resistor R3 are connected in series, the electrical connection point between the resistor R1 and the resistor R3 is coupled to the input end of the operational amplifier A1, the other end of the resistor R3 is coupled to the output end of the operational amplifier A1, and the other ends of the two resistors R1 are respectively a first common-mode output end and a second common-mode output end.

3. A high voltage common mode loop control system according to claim 2, characterized in that: A resistor R2 is connected in series between the electrical connection point between the resistor R1 and the resistor R3 and the virtual short adjustment end.

4. A high voltage common mode loop control system according to claim 1, characterized in that: The high-voltage amplification module (2) comprises a first low-voltage control unit (21), a second low-voltage control unit (22) and a high-voltage amplification unit (23); the first low-voltage control unit (21) and the second low-voltage control unit (22) are both coupled to the output end of the low-voltage amplification module (1); the first low-voltage control unit (21) is coupled between one input end of the high-voltage amplification unit (23) and a voltage source VIN respectively to control the on-off electrical connection between the high-voltage amplification unit (23) and the voltage source VIN; the second low-voltage control unit (22) is coupled between another input end of the high-voltage amplification unit (23) and a voltage source VIP respectively to control the on-off electrical connection between the high-voltage amplification unit (23) and the voltage source VIP; the first differential output end and the second differential output end are located on the high-voltage amplification unit (23).

5. A high voltage common mode loop control system according to claim 4, characterized in that: The high-voltage amplification unit (23) is a differential operational amplifier A3.

6. A high voltage common mode loop control system according to claim 5, characterized in that: The first low-voltage control unit (21) comprises a low-voltage operational amplifier A4, a resistor R4 and a field effect transistor Q1. The output end of the low-voltage amplifier module (1) is coupled to the resistor R4, the other end of the resistor R4 is coupled to the input end of the low-voltage operational amplifier A4, the other input end of the low-voltage operational amplifier A4 is connected to a voltage VRFEF, the output end of the low-voltage operational amplifier A4 is coupled to the gate of the field effect transistor Q1, the drain of the field effect transistor Q1 is coupled to the differential operational amplifier A3, and the source of the field effect transistor Q1 is coupled to a voltage source VIN.

7. A high voltage common mode loop control system according to claim 6, characterized in that: A resistor R6 is connected in series between the source of the field effect transistor Q1 and the voltage source VIN.

8. A high voltage common mode loop control system according to claim 5, characterized in that: The second low-voltage control unit (22) comprises a low-voltage operational amplifier A5, a resistor R5 and a field effect transistor Q2. The output end of the low-voltage amplifier module (1) is coupled to the resistor R5, the other end of the resistor R5 is coupled to the input end of the low-voltage operational amplifier A5, the other input end of the low-voltage operational amplifier A5 is connected to a voltage VRFEF, the output end of the low-voltage operational amplifier A5 is coupled to the gate of the field effect transistor Q2, the source of the field effect transistor Q2 is coupled to a voltage source VIP, and the drain of the field effect transistor Q2 is coupled to the differential operational amplifier A3.

9. A high voltage common mode loop control system according to claim 8, characterized in that: A resistor R7 is connected in series between the source of the field effect transistor Q2 and the voltage source VIP.

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