Resistance trimming circuit and electronic equipment

Abstract

The invention provides a resistor trimming circuit which comprises a high-precision resistor, the first end of the high-precision resistor is coupled to the first end of a current source module and the inverted input end of a comparator, the first end of the high-precision resistor receives first current, the second end of the high-precision resistor is grounded, and the inverted input end of the comparator receives reference voltage; the first end of the to-be-trimmed resistor is coupled to the second end of the current source module and the normal phase input end of the comparator, the first end of the to-be-trimmed resistor receives the second current, the second end of the to-be-trimmed resistor is grounded, and the normal phase input end of the comparator receives the first voltage; the output end of the comparator is coupled to the first input end of the trimming resistance network module; and the trimming resistor network module is connected in series or in parallel with the resistor to be trimmed. The first voltage is trimmed towards the reference voltage direction by adjusting the resistance value in the trimming resistor network module, so that the error of the resistance value of the branch circuit where the resistor to be trimmed is located is corrected, and the precision of the resistance value of the branch circuit where the resistor to be trimmed is located is improved.

Description

Technical Field

[0001] The present invention relates to the field of power electronics, and particularly to a resistor trimming circuit and an electronic device. Background Art

[0002] Using resistors with higher precision can improve the stability and accuracy of the entire circuit. Therefore, in integrated circuits, resistors with higher precision are often required. However, the manufacturing cost of a single resistor with higher precision is relatively high.

[0003] Integrated circuits have the advantage of process consistency, and thus it is more convenient to manufacture resistors with higher precision in integrated circuits. However, the resistors in integrated circuits are also easily affected by various factors. For example, errors in actual production, different process environments where the circuit is located, and the influence of the electric field on the resistor, etc., will all cause relatively large errors in the resistor.

[0004] Therefore, how to correct the error of the resistor value in the circuit and improve the precision of the resistor value in the circuit has become a technical problem that the industry urgently needs to solve at present. Summary of the Invention

[0005] The present invention provides a resistor trimming circuit and its electronic device, aiming to correct the error of the resistor value in the circuit and improve the precision of the resistor value in the circuit.

[0006] According to a first aspect of the present invention, an embodiment of the present invention provides a resistor trimming circuit, including: a current source module, a comparator, a trimming resistor network module, a high-precision resistor, and a resistor to be trimmed;

[0007] A first end of the current source module is coupled to a first end of the high-precision resistor, and is configured to output a first current. The first end of the high-precision resistor is further coupled to an inverting input terminal of the comparator, and is configured to input a reference voltage to the inverting input terminal of the comparator. A second end of the high-precision resistor is grounded;

[0008] A second end of the current source module is coupled to a first end of the resistor to be trimmed, and is configured to output a second current. The first end of the resistor to be trimmed is further coupled to a non-inverting input terminal of the comparator, and is configured to input a first voltage to the non-inverting input terminal of the comparator. A second end of the resistor to be trimmed is grounded;

[0009] An output terminal of the comparator is coupled to a first input terminal of the trimming resistor network module, and is configured to output a first signal to the trimming resistor network module. The first signal includes comparison result information of the resistance value of the branch where the resistor to be trimmed is located and the resistance value of the external circuit;

[0010] The trimming resistor network module is connected in series or in parallel with the resistor to be trimmed, and is used to adjust the resistance value inside the trimming resistor network module based on the first signal, so that the first voltage approaches the reference voltage.

[0011] Optionally, the resistor trimming circuit further includes a trimming bit generation module;

[0012] The enable terminal of the trimming bit generation module receives an enable control signal, the first input terminal of the trimming bit generation module receives a clock signal, the second input terminal receives the first signal, and the output terminal of the trimming bit generation module is coupled to the input terminal of the trimming resistor network module, and the output terminal outputs a resistance value control signal;

[0013] The trimming bit generation module is configured to:

[0014] When the enable control signal indicates enable, based on the first signal and the clock signal, output the output resistance value control signal to the trimming resistor network module to adjust the resistance value inside the trimming resistor network module.

[0015] Optionally, if the resistance value control signal is a bit signal, the method for outputting the output resistance value control signal to the trimming resistor network module based on the first signal and the clock signal includes:

[0016] When the clock signal is at the rising edge, if the resistor to be trimmed is less than the high-precision resistor and the first signal indicates that the first voltage is less than the reference voltage, control the bit value of the resistance value control signal to gradually increase until the first signal indicates that the first voltage is greater than or equal to the reference voltage;

[0017] When the clock signal is at the rising edge, if the resistor to be trimmed is greater than the high-precision resistor and the first signal indicates that the first voltage is greater than the reference voltage, control the bit value of the resistance value control signal to gradually increase until the first signal indicates that the first voltage is less than or equal to the reference voltage.

[0018] Optionally, the trimming resistor network module includes a trimming resistor array, and the trimming resistor array includes N trimming resistors, where N is an integer and N≥2;

[0019] The trimming resistor network module is further configured to:

[0020] Based on the bit value of the resistance value control signal, control the number of trimming resistors connected in series or in parallel with the resistor to be trimmed.

[0021] Optionally, the trimming resistor network module includes a series trimming resistor array and a first data selector module;

[0022] The series trimming resistor array includes N trimming resistors and N first switching transistors connected in series with the resistor to be trimmed in sequence. The first end of the i-th trimming resistor is coupled to the first input terminal through the corresponding first switching transistor, where i is an integer and N ≥ i ≥ 1;

[0023] The input terminal of the first data selector module receives the output resistance control signal, and its output terminal is respectively coupled to the control terminals of the N first switching transistors;

[0024] The first data selector module is configured to:

[0025] Based on the change of the bit value of the resistance control signal, control the number of the trimming resistors connected in series with the resistor to be trimmed.

[0026] Optionally, the trimming resistor network module includes a parallel trimming resistor array and a second data selector module;

[0027] The parallel trimming resistor array includes N trimming resistors and N second switching transistors respectively connected in parallel with the resistor to be trimmed, and each second switching transistor is disposed between the corresponding trimming resistor and the resistor to be trimmed;

[0028] The input terminal of the second data selector module receives the output resistance control signal, and its output terminal is respectively coupled to the control terminals of the N second switching transistors;

[0029] The second data selector module is configured to:

[0030] Based on the change of the bit value of the resistance control signal, control the number of the trimming resistors connected in parallel with the resistor to be trimmed.

[0031] Optionally, the enable terminal of the comparator and the enable terminal of the trimming resistor network module receive the enable control signal,

[0032] The comparator is further configured to:

[0033] When the enable control signal indicates enable, control the comparator to start working based on the enable control signal

[0034] The trimming resistor network module is configured to:

[0035] When the enable control signal indicates disable, control the number of the trimming resistors connected in series or in parallel with the resistor to be trimmed by the trimming resistor network module to be zero based on the enable control signal.

[0036] Optionally, the trimming bit generation module is further configured to:

[0037] When the enable control signal is characterized as off, control the bit value of the resistance control signal to zero based on the enable control signal.

[0038] Optionally, the first current is equal to the second current, and the resistance value of the branch where the resistor to be trimmed is located is equal to the resistance value of the high-precision resistor.

[0039] Optionally, the first current is not equal to the second current, and the ratio of the resistance value of the branch where the resistor to be trimmed is located to the resistance value of the high-precision resistor is equal to the ratio of the first current to the second current.

[0040] According to a second aspect of the present invention, there is provided an electronic device including the resistance trimming circuit described in the first aspect above.

[0041] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0042] A resistance trimming circuit and an electronic device provided by the present invention include: a high-precision resistor, whose first end is coupled to the first end of the current source module and the inverting input terminal of the comparator, the first end receives a first current, the second end is grounded, and the inverting input terminal of the comparator receives a reference voltage; a resistor to be trimmed, whose first end is coupled to the second end of the current source module and the non-inverting input terminal of the comparator, the first end receives a second current, the second end is grounded, and the non-inverting input terminal of the comparator receives a first voltage; the output terminal of the comparator is coupled to the first input terminal of the trimming resistor network module; the trimming resistor network module is in series or parallel with the resistor to be trimmed. By adjusting the resistance value inside the trimming resistor network module, the present invention trims the first voltage towards the reference voltage direction, thereby correcting the error of the resistance value of the branch where the resistor to be trimmed is located, and improving the resistance value accuracy of the branch where the resistor to be trimmed is located.

[0043] Furthermore, the present invention only needs to use one high-precision resistor. By adjusting the ratio of the first current to the second current, the resistance value of the branch where the resistor to be trimmed is located can be trimmed to any high-precision resistance value, thereby achieving a resistor with any resistance value and high precision at a low cost.

[0044] Furthermore, when the enable control signal is characterized as zero, the present invention zeros the number of resistors in the trimming resistor network module that are in series or parallel with the resistor to be trimmed, enabling the resistance trimming circuit to have a repeated trimming function, avoiding the trimming error of the resistance trimming circuit, and improving the stability of the resistance trimming circuit. Description of the Drawings

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0046] Figure 1 Structural schematic diagram of the resistance trimming circuit in the first embodiment of the present invention;

[0047] Figure 2 Structural schematic diagram of the resistance trimming circuit in the second embodiment of the present invention;

[0048] Figure 3 Structural schematic diagram of the resistance trimming circuit in the third embodiment of the present invention;

[0049] Figure 4 Structural schematic diagram of the series trimming resistor array in the embodiment of the present invention;

[0050] Figure 5 Structural schematic diagram of the parallel trimming resistor array in the embodiment of the present invention;

[0051] Figure 6 Structural schematic diagram of the resistance trimming circuit in the fourth embodiment of the present invention.

[0052] Figure 7 Structural schematic diagram of an electronic device in an embodiment of the present invention.

[0053] Description of the reference numerals:

[0054] 100 - Current source module;

[0055] 200 - Trimming resistor network module;

[0056] 300 - Trimming bit generation module;

[0057] 211 - Series trimming resistor array;

[0058] 212 - First data selection sub-module;

[0059] 221 - Parallel trimming resistor array;

[0060] 222 - Second data selection sub-module;

[0061] I1 - First current;

[0062] I2 - Second current;

[0063] CS - Enable control signal;

[0064] CLK - Clock signal;

[0065] Rset - High - precision resistor;

[0066] R - Resistor to be trimmed;

[0067] R0 - Trimming resistor;

[0068] S1 - First switching transistor;

[0069] S2 - Second switching transistor;

[0070] V1 - First voltage;

[0071] Verf - Reference voltage;

[0072] CMP - Comparator;

[0073] GND - Ground;

[0074] 400 - Operational amplifier;

[0075] R1 - First resistor;

[0076] V - Stable voltage. Detailed implementation manners

[0077] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0078] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above - mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non - exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0079] Next, the technical solutions of the present invention will be described in detail with specific embodiments. These several specific embodiments can be combined with each other, and for the same or similar concepts or processes, they may not be repeated in some embodiments.

[0080] Before filing this application, the applicant conducted thorough research on how to correct the error of the resistance value in the circuit and improve the accuracy of the resistance value in the circuit. For example, in a resistor trimming circuit, an efuse is often used to trim the resistor to be trimmed. Specifically, the fuse of the efuse is blown by generating a high level and a low level to control the number of trimming resistors electrically connected to the resistor to be trimmed, thereby completing the trimming of the resistor to be trimmed.

[0081] For the solution of using an efuse circuit to trim resistors, each fuse needs to be coupled to a comparator to determine whether each fuse needs to be blown. Therefore, the area required to implement the fuse blowing control of the efuse circuit is relatively large. Moreover, the efuse circuit can only be trimmed once, and there will be phenomena such as miswriting and non-blowing during the trimming process. Therefore, when the efuse circuit trims the resistor to be trimmed, there is a trimming error.

[0082] In view of this, the present invention provides a resistor trimming circuit, including: a current source module, a comparator, a trimming resistor network module, a high-precision resistor, and a resistor to be trimmed;

[0083] The first end of the current source module is coupled to the first end of the high-precision resistor for outputting a first current. The first end of the high-precision resistor is also coupled to the inverting input terminal of the comparator for inputting a reference voltage to the inverting input terminal of the comparator, and the second end of the high-precision resistor is grounded;

[0084] The second end of the current source module is coupled to the first end of the resistor to be trimmed for outputting a second current. The first end of the resistor to be trimmed is also coupled to the non-inverting input terminal of the comparator for inputting a first voltage to the non-inverting input terminal of the comparator, and the second end of the resistor to be trimmed is grounded;

[0085] The output terminal of the comparator is coupled to the first input terminal of the trimming resistor network module for outputting a first signal to the trimming resistor network module. The first signal includes the comparison result information of the resistance value of the branch where the resistor to be trimmed is located and the resistance value of the external circuit;

[0086] The trimming resistor network module is connected in series or in parallel with the resistor to be trimmed, and is used to adjust the resistance value inside the trimming resistor network module based on the first signal, so that the first voltage approaches the reference voltage.

[0087] It can be seen that the present invention only uses one comparator to compare the reference voltage with the first voltage, and obtains the comparison result information of the resistance value of the branch where the resistor to be trimmed is located and the resistance value of the external circuit. The trimming resistor network module adjusts the internal resistance value based on the comparison result information, and trims the first voltage towards the reference voltage, thereby realizing the correction of the resistance value error of the branch where the resistor to be trimmed is located with a relatively simple circuit and a small area, and improving the accuracy of the resistance value of the branch where the resistor to be trimmed is located.

[0088] To make the above objects, features, and beneficial effects of the present invention more obvious and understandable, the following detailed description will be given to the specific embodiments of the present invention with reference to the accompanying drawings.

[0089] Please refer to Figure 1 , Figure 1 , which shows the situation where the trimming resistor network module is connected in series with the resistor to be trimmed. It can be seen that the resistor trimming circuit of the present invention includes: a current source module 100, a comparator CMP, a trimming resistor network module 200, a high-precision resistor Rset, and a resistor to be trimmed R;

[0090] The first end of the current source module 100 is coupled to the first end of the high-precision resistor Rset for outputting a first current I1. The first end of the high-precision resistor Rset is also coupled to the inverting input terminal of the comparator CMP for inputting a reference voltage Verf to the inverting input terminal of the comparator CMP. The second end of the high-precision resistor Rset is grounded to GND;

[0091] The second end of the current source module 100 is coupled to the first end of the resistor to be trimmed R for outputting a second current I2. The first end of the resistor to be trimmed R is also coupled to the non-inverting input terminal of the comparator CMP for inputting a first voltage V1 to the non-inverting input terminal of the comparator CMP. The second end of the resistor to be trimmed R is grounded to GND;

[0092] The output terminal of the comparator CMP is coupled to the first input terminal of the trimming resistor network module 200 for outputting a first signal to the trimming resistor network module 200. The first signal includes the comparison result information of the resistance value of the branch where the resistor to be trimmed R is located and the resistance value of the external circuit;

[0093] The trimming resistor network module 200, which is connected in series with the resistor to be trimmed R, is used to adjust the internal resistance value of the trimming resistor network module 200 based on the first signal.

[0094] In a preferred embodiment, the error range between the actual resistance value and the ideal resistance value of the high-precision resistor is: ±1% of the ideal resistance value of the high-precision resistor. It should be understood that the present invention is not limited thereto, and those skilled in the art can select the precision of the high-precision resistor according to needs.

[0095] The higher the precision of the high-precision resistor Rset, the higher the precision of the resistance value of the branch where the resistor to be repaired R is located. However, in the specific manufacturing process, it is difficult to obtain a resistor with an error of zero between the actual resistance value and the ideal resistance value. Therefore, the error range between the ideal resistance values of the high-precision resistor is set to: ±1% of the ideal resistance value of the high-precision resistor. A resistor with relatively high precision can be obtained in a specific embodiment.

[0096] It can be seen that the present invention only uses one comparator to compare the reference voltage with the first voltage to obtain the comparison result information of the resistance value of the branch where the resistor to be trimmed is located and the resistance value of the external circuit. The trimming resistor network module trims the internal resistance value based on the comparison result information, trimming the first voltage towards the reference voltage direction, realizing the correction of the error of the resistance value of the branch where the resistor to be trimmed is located with a relatively simple circuit and a small area, and improving the precision of the resistance value of the branch where the resistor to be trimmed is located.

[0097] In a specific embodiment, please continue to refer to Figure 1 , the first current I1 is equal to the second current I2, and the resistance value of the branch where the resistor to be trimmed R is located is equal to the resistance value of the high-precision resistor Rset.

[0098] Among them, in this embodiment, a resistor with a relatively high precision and the same resistance value as the high-precision resistor Rset can be obtained.

[0099] In another specific embodiment, please continue to refer to Figure 1 , the first current I1 may not be equal to the second current I2, and the ratio of the resistance value of the branch where the resistor to be trimmed R is located to the resistance value of the high-precision resistor Rset is equal to the ratio of the first current I1 to the second current I2.

[0100] It can be seen that this embodiment only requires a high-precision resistor with relatively high precision. By adjusting the ratio of the first current to the second current, the resistance value of the branch where the resistor to be trimmed is located can be trimmed to any high-precision resistance value at a relatively low cost.

[0101] In another embodiment, please refer to Figure 2 , Figure 2The situation where the trimming resistor network module 200 is connected in parallel with the resistor R to be trimmed is shown. The trimming resistor network module is used to adjust the resistance value inside the trimming resistor network module 200 based on the first signal.

[0102] Among them, Figure 2 other parts of the resistor trimming circuit are exactly the same as Figure 1 the resistor trimming circuit shown, and the present invention will not elaborate here.

[0103] In a specific embodiment, please refer to Figure 3 , the resistor trimming circuit further includes a trimming bit generation module 300;

[0104] The enable terminal of the trimming bit generation module 300 receives an enable control signal CS. The first input terminal of the trimming bit generation module 300 receives a clock signal CLK, the second input terminal receives the first signal, and the output terminal of the trimming bit generation module 300 is coupled to the input terminal of the trimming resistor network module 200, and the output terminal outputs a resistance value control signal;

[0105] The trimming bit generation module 300 is configured to:

[0106] When the enable control signal CS indicates enable, based on the first signal and the clock signal CLK, output the output resistance value control signal to the trimming resistor network module 200 to adjust the resistance value inside the trimming resistor network module 200.

[0107] In a specific embodiment, if the resistance value control signal is a bit signal, the method for outputting the output resistance value control signal to the trimming resistor network module based on the first signal and the clock signal includes:

[0108] When the clock signal is at the rising edge, if the resistor to be trimmed is less than the high-precision resistor and the first signal indicates that the first voltage is less than the reference voltage, control the bit value of the resistance value control signal to gradually increase until the first signal indicates that the first voltage is greater than or equal to the reference voltage;

[0109] When the clock signal is at the rising edge, if the resistor to be trimmed is greater than the high-precision resistor and the first signal indicates that the first voltage is greater than the reference voltage, control the bit value of the resistance value control signal to gradually increase until the first signal indicates that the first voltage is less than or equal to the reference voltage.

[0110] Among them, the method of outputting the output resistance control signal to the trimming resistor network module 200 based on the first signal and the clock signal can be, for example, when the clock signal is at the rising edge, if the resistor to be trimmed is less than the high-precision resistor and the first signal indicates that the first voltage is less than the reference voltage, then control the bit value of the resistance control signal to change from 00000000 → 00000001 →... → 11111111 until the first signal indicates that the first voltage is greater than or equal to the reference voltage, and then fix the bit value of the resistance control signal.

[0111] Among them, the method of outputting the output resistance control signal to the trimming resistor network module 200 based on the first signal and the clock signal can also be, for example, when the clock signal is at the rising edge, if the resistor to be trimmed is greater than the high-precision resistor and the first signal indicates that the first voltage V1 is greater than the reference voltage, then control the bit value of the resistance control signal to change from 00000000 → 00000001 →... → 11111111 until the first signal indicates that the first voltage is less than or equal to the reference voltage, and then fix the bit value of the resistance control signal.

[0112] Now, the internal structure of the trimming resistor network module will be further elaborated.

[0113] In one embodiment, the trimming resistor network module includes a trimming resistor array, and the trimming resistor array includes N trimming resistors, where N is an integer and N ≥ 2;

[0114] The trimming resistor network module is further configured to:

[0115] Based on the bit value of the resistance control signal, control the number of trimming resistors connected in series or in parallel with the resistor to be trimmed. Among them, as an example, if the bit value of the resistance control signal gradually increases from 00000000 → 00000001, then control the number of trimming resistors R0 connected in series or in parallel with the resistor to be trimmed R to increase from zero to one. If the bit value of the resistance control signal is fixed at 00000001, then control the number of trimming resistors R0 connected in series or in parallel with the resistor to be trimmed R to remain unchanged.

[0116] In a specific embodiment, in the case where the trimming resistor network module is connected in series with the resistor to be trimmed, please refer to Figure 4 , the trimming resistor network module 200 includes a series trimming resistor array 211 and a first data selection sub-module;

[0117] The series trimming resistor array 211 includes N trimming resistors connected in series with the resistor R to be trimmed and N first switching transistors S1. The first end of each trimming resistor is coupled to the first input terminal through the corresponding first switching transistor S1;

[0118] The input terminal of the first data selection sub-module 212 receives the output resistance control signal, and its output terminal is respectively coupled to the control terminals of the N first switching transistors S1;

[0119] The first data selection sub-module 212 is configured as:

[0120] Based on the change in the bit value of the resistance control signal, control the number of the trimming resistors R0 connected in series with the resistor R to be trimmed.

[0121] As a preferred embodiment, in Figure 4 the example of, the resistance value range of the trimming resistor R0 is: ±1% of the ideal resistance value of the high-precision resistor Rset. Of course, it should be understood that the present invention is not limited thereto, and those skilled in the art of the present invention can select the trimming resistor R0 with a suitable resistance value according to needs.

[0122] Among them, the smaller the resistance value of the trimming resistor R0, the higher the accuracy of the resistor obtained in this embodiment. However, when the resistance value of the trimming resistor R0 is very small, a large number of bits are required to make the first voltage greater than or equal to the reference voltage. Therefore, the resistance value range of the trimming resistor is set to: ±1% of the resistance value of the high-precision resistor. It is realized that a resistor with higher accuracy can be obtained only with a smaller number of bits.

[0123] Among them, the specific implementation manner of controlling the number of the trimming resistors R0 connected in series with the resistor R to be trimmed based on the change in the bit value of the resistance control signal. For example, if the bit value of the resistance control signal changes from 00000000 to 00000001, the first data selection sub-module 212 controls the on and off of the first switching transistor S1 to control the number of the trimming resistors R0 connected in series with the resistor Rset to change from 0 to one.

[0124] When the trimming resistor network module is in parallel with the resistor R to be trimmed, please refer to Figure 5 , in one embodiment, the trimming resistor network module 200 includes a parallel trimming resistor array 221 and a second data selection sub-module 222;

[0125] The parallel trimming resistor array 221 includes N trimming resistors R0 respectively connected in parallel with the resistor R to be trimmed, and N second switching transistors S2. Each second switching transistor S2 is disposed between the corresponding trimming resistor R0 and the resistor R to be trimmed;

[0126] The input terminal of the second data selection sub-module 222 receives the output resistance control signal, and its output terminal is respectively coupled to the control terminals of N second switching transistors S2;

[0127] The second data selection sub-module 222 is configured to:

[0128] Based on the change in the bit value of the resistance control signal, control the number of trimming resistors R0 connected in parallel with the resistor R to be trimmed.

[0129] As a preferred embodiment, in Figure 5 the example of, the resistance value range of the trimming resistor R0 is: ±1% of the ideal resistance value of the high-precision resistor Rset. Of course, it should be understood that the present invention is not limited thereto, and those skilled in the art of the present invention can select the trimming resistor R0 with a suitable resistance value according to needs.

[0130] Among them, the smaller the resistance value of the trimming resistor R0, the higher the precision of the resistor obtained in this embodiment. However, when the resistance value of the trimming resistor R0 is very small, a large number of bits are required to make the first voltage less than or equal to the reference voltage. Therefore, the resistance value range of the trimming resistor is set to: ±1% of the resistance value of the high-precision resistor. Only a relatively small number of bits are required to obtain a resistor with higher precision.

[0131] Among them, based on the change in the bit value of the resistance control signal, the specific implementation manner of controlling the number of trimming resistors R0 connected in series with the resistor R to be trimmed, for example, if the bit value of the resistance control signal changes from 00000000 to 00000001, the second data selection sub-module 222 controls the number of trimming resistors R0 connected in parallel with the resistor Rset to change from 0 to one by controlling the conduction and cutoff of the second switching transistor S2.

[0132] As a preferred embodiment, please refer to Figure 6 , the enable terminal of the comparator CMP and the enable terminal of the trimming resistor network module 200 receive the enable control signal CS,

[0133] The comparator CMP is further configured to:

[0134] When the enable control signal CS indicates enabling, control the comparator CMP to start working based on the enable control signal CS;

[0135] The trimming resistor network module 200 is configured to:

[0136] When the enable control signal CS is characterized as off, based on the enable control signal CS, the number of trimming resistors R0 in series or parallel with the trimming resistor network module 200 and the resistor to be trimmed Rset is zero.

[0137] Wherein, in this embodiment, when the enable control signal CS is characterized as off, the number of trimming resistors R0 in series or parallel with the resistor to be trimmed is zero, and when the enable control signal CS is characterized as enabled, based on the enable control signal CS, the comparator CMP is controlled to start working. Thus, the resistor trimming resistor has the function of repeated trimming, avoiding errors during the trimming process and improving the stability of the resistor trimming circuit.

[0138] As an alternative embodiment, please continue to refer to Figure 6 The trimming bit generation module 300 is further configured to:

[0139] When the enable control signal CS is characterized as off, based on the enable control signal CS, the bit value of the resistance value control signal is set to zero.

[0140] Wherein, by the trimming bit generation module 300, when the enable control signal CS is characterized as off, based on the enable control signal CS, the bit value of the resistance value control signal is set to zero, which can reuse the bit positions during previous trimming during repeated trimming, reducing the bit area required for this embodiment.

[0141] In summary, the embodiment of the present invention provides a resistor trimming circuit including: a high-precision resistor, whose first end is coupled to the first end of the current source module and the inverting input terminal of the comparator, the first end receives a first current, the second end is grounded, and the inverting input terminal of the comparator receives a reference voltage; a resistor to be trimmed, whose first end is coupled to the second end of the current source module and the non-inverting input terminal of the comparator, the first end receives a second current, the second end is grounded, and the non-inverting input terminal of the comparator receives a first voltage; the output terminal of the comparator is coupled to the first input terminal of the trimming resistor network module; the trimming resistor network module is in series or parallel with the resistor to be trimmed, adjusts the resistance value inside the trimming resistor network module, and trims the first voltage towards the reference voltage, thereby correcting the error of the resistance value of the branch where the resistor to be trimmed is located with a relatively simple circuit and a small area, and improving the accuracy of the resistance value of the branch where the resistor to be trimmed is located.

[0142] In addition, the present invention also provides an electronic device, and the electronic device includes the above-mentioned resistor trimming circuit.

[0143] As an example, please refer to Figure 7 The resistor trimming circuit of the present invention can be applied to a negative feedback regulation circuit, including:

[0144] The above-mentioned resistor trimming circuit ( Figure 7 in Figure 6 the example of the resistor trimming circuit shown);

[0145] An operational amplifier 400, the non-inverting input terminal of the operational amplifier 400 receives a stable voltage V, and its output terminal is coupled to the first end of a first resistor R1, and the second end of the first resistor is coupled to the inverting input terminal of the operational amplifier and the first end of the resistor R to be trimmed.

[0146] In Figure 7 the example of, the resistor trimming circuit provided by the present invention can ensure that the voltage output by the operational amplifier has an accurate voltage value.

[0147] In other embodiments, the electronic device may be a voltage testing device, a power management device, etc. The present invention is not limited thereto, and it may also be other devices that require a resistor divider.

[0148] In summary, in the embodiment of the present invention, a high-precision resistor is provided in the circuit. Its first end is coupled to the first end of the current source module and the inverting input terminal of the comparator. Its first end receives a first current, and its second end is grounded. The inverting input terminal of the comparator receives a reference voltage; a resistor to be trimmed, its first end is coupled to the second end of the current source module and the non-inverting input terminal of the comparator. Its first end receives a second current, and its second end is grounded. The non-inverting input terminal of the comparator receives a first voltage; the output terminal of the comparator is coupled to the first input terminal of the trimming resistor network module; the trimming resistor network module is connected in series or in parallel with the resistor to be trimmed. By adjusting the resistance value inside the trimming resistor network module, the first voltage is trimmed towards the reference voltage direction. Thus, the error of the resistance value of the branch where the resistor to be trimmed is located is corrected, and the resistance value accuracy of the branch where the resistor to be trimmed is located is improved.

[0149] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A resistance trimming circuit, characterized in that: include: Current source module, comparator, trimming resistor network module, high-precision resistor and resistor to be trimmed; The first end of the current source module is coupled to the first end of the high-precision resistor for outputting a first current. The first end of the high-precision resistor is also coupled to the inverting input end of the comparator for inputting a reference voltage to the inverting input end of the comparator. The second end of the high-precision resistor is grounded. The second end of the current source module is coupled to the first end of the resistor to be adjusted, for outputting a second current. The first end of the resistor to be adjusted is also coupled to the non-inverting input end of the comparator, for inputting a first voltage to the non-inverting input end of the comparator. The second end of the resistor to be adjusted is grounded. The output end of the comparator is coupled to the first input end of the trimming resistor network module, and is used to output a first signal to the trimming resistor network module, wherein the first signal includes comparison result information between the resistance value of the branch where the resistor to be trimmed is located and the resistance value of the external circuit; The trimming resistor network module is connected in series with the resistor to be trimmed, or in parallel with the resistor to be trimmed, and is used to adjust the resistance value inside the trimming resistor network module based on the first signal so that the first voltage approaches the reference voltage.

2. The resistance trimming circuit according to claim 1, wherein: The resistance trimming circuit also includes a trimming bit generation module; The enable terminal of the trimming bit generation module receives an enable control signal, the first input terminal of the trimming bit generation module receives a clock signal, the second input terminal receives the first signal, the output terminal of the trimming bit generation module is coupled to the input terminal of the trimming resistor network module, and the output terminal outputs a resistance control signal; The trim bit generation module is configured as follows: When the enable control signal is characterized as enabled, the output resistance control signal is output to the trimming resistor network module based on the first signal and the clock signal to adjust the resistance value inside the trimming resistor network module.

3. The resistance trimming circuit according to claim 2, wherein: The resistance control signal is a bit signal, and the method of outputting the output resistance control signal to the trimming resistor network module based on the first signal and the clock signal includes: When the clock signal is at a rising edge, if the resistance to be trimmed is smaller than the high-precision resistance, and the first signal indicates that the first voltage is smaller than the reference voltage, the bit value of the resistance control signal is controlled to increase gradually until the first signal indicates that the first voltage is greater than or equal to the reference voltage; When the clock signal is at a rising edge, if the resistance to be trimmed is greater than the high-precision resistance, and the first signal indicates that the first voltage is greater than the reference voltage, the bit value of the resistance control signal is controlled to increase gradually until the first signal indicates that the first voltage is less than or equal to the reference voltage.

4. The resistance adjustment circuit according to claim 3, wherein: The trimming resistor network module includes a trimming resistor array, and the trimming resistor array includes N trimming resistors, wherein N is an integer, and N≥2; The trimming resistor network module is further configured as: Based on the bit value of the resistance control signal, the number of the trimming resistors connected in series or in parallel with the resistor to be trimmed is controlled.

5. The resistance trimming circuit according to claim 4, wherein: The trimming resistor network module includes a series trimming resistor array and a first data selection submodule; The series trimming resistor array includes N trimming resistors and N first switch tubes which are sequentially connected in series with the resistor to be trimmed, and the first end of the i-th trimming resistor is coupled to the first input end through the corresponding first switch tube, wherein i is an integer, and N≥i≥1; The input end of the first data selection submodule receives the output resistance control signal, and the output end thereof is respectively coupled to the control ends of the N first switch tubes; The first data selection submodule is configured as follows: Based on the bit value change of the resistance control signal, the number of the trimming resistors connected in series with the resistor to be trimmed is controlled.

6. The resistance trimming circuit according to claim 4, wherein: The trimming resistor network module includes a parallel trimming resistor array and a second data selection submodule; The parallel trimming resistor array includes N trimming resistors respectively connected in parallel with the resistors to be trimmed, and N second switch tubes, each of which is arranged between the corresponding trimming resistor and the resistor to be trimmed; The input end of the second data selection submodule receives the output resistance control signal, and the output end thereof is respectively coupled to the control ends of the N second switch tubes; The second data selection submodule is configured as follows: Based on the bit value change of the resistance control signal, the number of the trimming resistors connected in parallel with the resistor to be trimmed is controlled.

7. The resistance trimming circuit according to claim 2, wherein: The enable terminal of the comparator and the enable terminal of the trimming resistor network module receive the enable control signal, The comparator is further configured to: When the enable control signal is characterized as enabled, the comparator is controlled to start working based on the enable control signal The trimming resistor network module is configured as follows: When the enable control signal is characterized as being off, the number of the trimming resistors connected in series or in parallel with the resistor to be trimmed by controlling the trimming resistor network module based on the enable control signal is zero.

8. The resistance trimming circuit according to claim 2, wherein: The trimming bit generation module is further configured to: When the enable control signal is characterized as being off, the bit value of the resistance control signal is controlled to return to zero based on the enable control signal.

9. The resistance trimming circuit according to claim 1, wherein: The first current is equal to the second current, and the resistance value of the branch where the resistor to be adjusted is located is equal to the resistance value of the high-precision resistor.

10. The resistance trimming circuit according to claim 1, wherein: The first current is not equal to the second current, and the ratio of the resistance of the branch where the resistor to be adjusted is located to the resistance of the high-precision resistor is equal to the ratio of the first current to the second current.

11. An electronic device, characterized in that: The invention comprises the resistance adjustment circuit as described in any one of claims 1 to 10.

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