Voltage conversion circuit and electronic device

By setting a modulation switch in the voltage conversion circuit and using PWM signal modulation, the problem of nonlinear error in the DAC circuit is solved, improving the DAC accuracy without increasing the circuit area.

CN224401528UActive Publication Date: 2026-06-23SHENZHEN SINONE CHIP ELECTRONIC CO. LTD.
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
SHENZHEN SINONE CHIP ELECTRONIC CO. LTD.
Filing Date
2025-07-07
Publication Date
2026-06-23

AI Technical Summary

Technical Problem

Existing technologies struggle to accurately compensate for the nonlinear errors in DAC circuits, thus affecting DAC accuracy.

Method used

A voltage conversion circuit is employed, including a controller, a terminating resistor, multiple first resistors, multiple second resistors, and multiple control switches. By setting a modulation switch to receive a modulation signal to cancel nonlinear errors, a PWM signal and a reference voltage are used for precision modulation.

Benefits of technology

It improves the accuracy of the DAC without increasing the circuit area, and can perform precision modulation based on the nonlinear error of the voltage conversion circuit.

✦ Generated by Eureka AI based on patent content.

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Abstract

This application provides a voltage conversion circuit and electronic device, including: a controller, a terminating resistor, a plurality of first resistors, a plurality of second resistors, and a plurality of control switches. The first end of the terminating resistor is grounded; the first resistors are connected in series, and the first end of the first first resistor is connected to the second end of the terminating resistor; the first end of one second resistor is connected to the first end of the first first resistor, and the first end of each of the other second resistors is connected to the second end of the first resistor respectively; the first end of each control switch is connected to the second end of one of the second resistors respectively, and the second end of the control switch is connected to or grounded to a preset reference voltage according to a control signal sent by the controller; one of the plurality of control switches is set as a modulation switch, which is used to receive a modulation signal sent by the controller, and both the modulation switch and the modulation signal are determined based on nonlinear error.
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Description

Technical Field

[0001] This utility model relates to the technical field of integrated circuits, and more particularly to a voltage conversion circuit and electronic device. Background Technology

[0002] Currently, DACs (Digital to Analog Converters) have many applications in display technology and signal transmission. To improve DAC accuracy, modifications are made to the DAC's hardware layout or overall modulation of the DAC's reference voltage. However, this approach struggles to precisely compensate for the nonlinear errors inherent in the DAC circuitry. Utility Model Content

[0003] The purpose of this invention is to provide a voltage conversion circuit and electronic device that aims to solve the problem of "difficulty in accurately offsetting the nonlinear error of DAC circuit" in the prior art.

[0004] This invention is implemented as follows: This invention provides a voltage conversion circuit, comprising:

[0005] Controller;

[0006] A terminating resistor, the first end of which is grounded;

[0007] Multiple first resistors are connected in series, with the first end of the first first resistor connected to the second end of the terminating resistor, and the second end of the last first resistor serving as the output terminal of the voltage conversion circuit.

[0008] Multiple second resistors, wherein the first end of one second resistor is connected to the first end of the first first resistor, and the first end of each of the other second resistors is connected to the second end of one of the first resistors respectively;

[0009] Multiple control switches are provided, with the controlled terminal of each control switch connected to the controller. The first terminal of each control switch is connected to the second terminal of a second resistor. The second terminal of each control switch is connected to or grounded according to the control signal sent by the controller.

[0010] In this configuration, one of the multiple control switches is configured as a modulation switch, which is used to receive a modulation signal sent by the controller. Both the modulation switch and the modulation signal are determined based on a pre-measured nonlinear error of the voltage conversion circuit.

[0011] In some embodiments, the modulation signal is a PWM signal, and the control signal includes a multi-bit level signal, with each second resistor corresponding to one bit of the level signal, and the sequence of the second resistor and the sequence of the corresponding control switch are the same as the sequence of the level signal.

[0012] In some embodiments, if the modulation switch is not the control switch of the first sequence position, then the control switch corresponding to the previous sequence position of the modulation switch is always grounded.

[0013] In some embodiments, each of the level signals is either high or low. When the level signal is high, the second terminal of the corresponding control switch is connected to the preset reference voltage. When the level signal is low, the second terminal of the corresponding control switch is grounded.

[0014] In some embodiments, the ratio of the resistance value of the first resistor to the resistance value of the second resistor is 1:2.

[0015] In some embodiments, the resistance value of the terminating resistor is the same as the resistance value of the second resistor.

[0016] This invention also provides an electronic device, including a voltage conversion circuit as described in any of the specifications.

[0017] In some embodiments, the resistance value of the terminating resistor is the same as the resistance value of the second resistor.

[0018] In some embodiments, the voltage conversion circuit further includes:

[0019] A voltage regulator capacitor, wherein the first terminal of the voltage regulator capacitor is connected to the second terminal of the last first resistor, and the second terminal of the voltage regulator capacitor is grounded;

[0020] A first incrementing resistor and a second incrementing resistor, wherein the first end of the first incrementing resistor is connected to the second end of the terminating resistor and the first end of the second incrementing resistor, respectively, and the second end of the first incrementing resistor is connected to the first end of the first resistor.

[0021] This invention provides a voltage conversion circuit, comprising: a controller, a terminating resistor, multiple first resistors, multiple second resistors, and multiple control switches. The first end of the terminating resistor is grounded. The multiple first resistors are connected in series, with the first end of the first first resistor connected to the second end of the terminating resistor, and the second end of the last first resistor serving as the output terminal of the voltage conversion circuit. The first end of one second resistor is connected to the first end of the first first resistor, and the first end of each of the other second resistors is connected to the second end of one of the first resistors. The controlled terminal of each control switch is connected to the controller, and the first end of each control switch is connected to the second end of one of the second resistors. The second end of the control switch is connected to or grounded according to a preset reference voltage based on a control signal sent by the controller. One of the multiple control switches is configured as a modulation switch, which receives a modulation signal sent by the controller. Both the modulation switch and the modulation signal are determined based on a pre-measured nonlinear error of the voltage conversion circuit. This circuit offers the following advantages: 1. Improved DAC accuracy without increasing circuit area; 2. Capable of precision modulation based on the nonlinear error of the voltage conversion circuit. Attached Figure Description

[0022] Figure 1 This is a circuit diagram of the first voltage conversion circuit provided in this embodiment of the present invention;

[0023] Figure 2 This is a circuit diagram of the second voltage conversion circuit provided in this embodiment of the present invention;

[0024] Figure 3 This is a waveform diagram of the output voltage of various digital-to-analog converters provided in the embodiments of this utility model;

[0025] Figure 4 This is a partial waveform diagram of the output voltage of two digital-to-analog converters provided in the embodiments of this utility model. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0027] The implementation of this utility model will be described in detail below with reference to specific embodiments.

[0028] This invention provides a voltage conversion circuit, comprising: a controller, a terminating resistor, multiple first resistors, multiple second resistors, and multiple control switches. The first end of the terminating resistor is grounded. The multiple first resistors are connected in series, with the first end of the first first resistor connected to the second end of the terminating resistor, and the second end of the last first resistor serving as the output terminal of the voltage conversion circuit. The first end of one second resistor is connected to the first end of the first first resistor, and the first end of each of the other second resistors is connected to the second end of one of the first resistors. The controlled end of each control switch is connected to the controller, and the first end of each control switch is connected to the second end of one of the second resistors. The second end of the control switch is connected to or grounded according to a control signal sent by the controller. One of the multiple control switches is configured as a modulation switch, which receives a modulation signal sent by the controller. Both the modulation switch and the modulation signal are determined based on a pre-measured nonlinear error of the voltage conversion circuit.

[0029] The voltage conversion circuit provided by this utility model can be used to convert binary code into a corresponding output voltage. For example, a 4-bit binary code, where the number of bits in the binary code is the same as the number of bits in the control signal of this utility model. The following will use a 4-bit binary code as an example to describe the voltage conversion circuit provided by this utility model in detail. It should be noted that the embodiments provided by this utility model are for detailed description only and are not intended to limit the scope of protection of this utility model.

[0030] like Figure 1 As shown, this utility model provides a first type of 4-bit voltage conversion circuit 100, including: a controller (not shown in the figure), a terminating resistor Rj, a plurality of first resistors (R10-R12), a plurality of second resistors (R20-R23), and a plurality of control switches (S0-S3).

[0031] The controller is an MCU or logic control circuit. The first terminal of the terminating resistor Rj is grounded. Multiple first resistors (R10-R12) are connected in series. The first terminal of the first first resistor R10 is connected to the second terminal of the terminating resistor Rj. The second terminal of the last first resistor R12 serves as the output terminal V of the voltage conversion circuit 100. OUTOne terminal of a second resistor R20 is connected to the first terminal of a first resistor R10. The first terminal of each of the other second resistors (R21-R23) is connected to the second terminal of a first resistor (R10-R12). The controlled terminal of each control switch (S0-S3) is connected to the controller. The first terminal of each control switch (S0-S3) is connected to the second terminal of a second resistor (R20-R23). The second terminal of each control switch (S0-S3) is connected to or grounded to a preset reference voltage Vref according to the control signal sent by the controller. One of the multiple control switches (S0-S3) is designated as a modulation switch Sn. The modulation switch Sn is used to receive the modulation signal sent by the controller. Both the modulation switch Sn and the modulation signal are determined based on the pre-measured nonlinear error of the voltage conversion circuit 100.

[0032] In some embodiments, the modulation signal is a PWM signal (hereinafter abbreviated as PWM). The PWM includes a multi-bit level signal, with each second resistor corresponding to a single level signal. The sequence of the second resistor and the sequence of the corresponding control switch are the same as the sequence of the level signal. For example, a 4-bit PWM includes: [a3 a2 a1 a0]. Then, a0 corresponds to the second resistor R20 and the control switch S0, a1 corresponds to the second resistor R21 and the control switch S1, and so on. a3, a2, a1, and a0 can all be 1 or 0.

[0033] In some embodiments, each level signal is either high or low. When the level signal is high, the second terminal of the corresponding control switch is connected to a preset reference voltage. When the level signal is low, the second terminal of the corresponding control switch is grounded.

[0034] In some embodiments, the ratio of the resistance value of the first resistor to the resistance value of the second resistor is 1:2.

[0035] In some embodiments, the resistance value of the terminating resistor is the same as the resistance value of the second resistor.

[0036] like Figure 1 In the voltage conversion circuit 100 shown, after the PWM signal is applied to modulate the modulation switch Sn, the error of the output voltage of the voltage conversion circuit 100 increases by 1 LSB, that is, the output voltage of the voltage conversion circuit 100 changes from [0, ] adjusted to [ , Here, N=4.

[0037] like Figure 1 As shown, the modulation switch Sn is the control switch S0. By adjusting the duty cycle of the PWM, the output voltage of the voltage conversion circuit 100 can be flexibly adjusted between 0 and 1 LSB.

[0038] In some embodiments, if the modulation switch Sn is not the control switch S0 of the first sequence position, the control switch corresponding to the previous sequence position of the modulation switch is always grounded.

[0039] like Figure 1 As shown, when using higher-order control switches (S1-S3) as modulation switches Sn, the next lowest-order switches need to be grounded. For example, when using PWM modulation control switch S2, control switch S1 is grounded; or, for example, when using PWM control switch S1, control switch S0 is grounded. This ensures that the ideal output point is located in the center of the adjustment range. For example, when using PWM modulation control switch S2, the adjustment range is -2 to +2 LSB; or, for example, when using PWM control switch S1, the adjustment range is -1 to +1 LSB.

[0040] If the output voltage error needs to be controlled within 2 LSB, 4 LSB, and 8 LSB, then PWM is needed to control control switches S1, S2, and S3 respectively.

[0041] like Figure 1 In the embodiment shown, the error of the voltage conversion circuit 100 is increased by 1 LSB by PWM. In order to adjust the error of the voltage conversion circuit 100 to ±0.5 LSB, an incrementing resistor needs to be introduced.

[0042] like Figure 2 As shown, the voltage conversion circuit 100 further includes: a voltage stabilizing capacitor C, a first step-up resistor 31, and a second step-up resistor 32. The first terminal of the voltage stabilizing capacitor C is connected to the second terminal of the last first resistor R12, and the second terminal of the voltage stabilizing capacitor C is grounded. The first terminal of the first step-up resistor 31 is connected to the second terminal of the terminating resistor Rj and the first terminal of the second step-up resistor 32, respectively, and the second terminal of the first step-up resistor 31 is connected to the first terminal of the first first resistor R0.

[0043] If the original output voltage of voltage conversion circuit 100 is [ , ],like Figure 2 The adjustment range of the voltage conversion circuit 100 shown is -0.5 to +0.5 LSB.

[0044] like Figure 2 As shown, the duty cycle of the PWM is defined as k, where, Let mis be the nonlinear error of the DAC. Then, the adjusted output voltage V' OUT for:

[0045] ;

[0046] Ideally, If the duty cycle k of the PWM is sufficiently fine, then... Therefore, the error of the voltage conversion circuit 100 can be infinitely small.

[0047] Please see Figure 3 , Figure 3 This is a schematic diagram of the output voltage waveforms of various digital-to-analog converters provided in embodiments of this application. For example... Figure 3 As shown, the digital control data for multiple digital-to-analog converters is all 0111, meaning the output... For example, waveforms of the original version (without PWM tuning), full-range tuning (with tuning of the reference voltage Vref), and clock tuning are given.

[0048] Assuming the voltage conversion circuit 100 exists in its original position 0111. Nonlinear errors, such as Figure 4 As shown, in the output voltage before and after adjustment, the unadjusted voltage contains... The nonlinear error.

[0049] This application also provides an electronic device, including a voltage conversion circuit as described in any of the embodiments of this utility model.

[0050] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A voltage conversion circuit, characterized in that, include: Controller; A terminating resistor, the first end of which is grounded; Multiple first resistors are connected in series, with the first end of the first first resistor connected to the second end of the terminating resistor, and the second end of the last first resistor serving as the output terminal of the voltage conversion circuit. Multiple second resistors, wherein the first end of one second resistor is connected to the first end of the first first resistor, and the first end of each of the other second resistors is connected to the second end of one of the first resistors respectively; Multiple control switches are provided, and the controlled terminal of each control switch is connected to the controller. The first terminal of each control switch is connected to the second terminal of a second resistor. The second terminal of each control switch is connected to or grounded according to the control signal sent by the controller. In this configuration, one of the multiple control switches is configured as a modulation switch, which is used to receive a modulation signal sent by the controller. Both the modulation switch and the modulation signal are determined based on a pre-measured nonlinear error of the voltage conversion circuit.

2. The voltage conversion circuit as described in claim 1, characterized in that, The modulation signal is a PWM signal, and the control signal includes a multi-bit level signal. Each second resistor corresponds to one bit of the level signal, and the sequence of the second resistor and the sequence of the corresponding control switch are the same as the sequence of the level signal.

3. The voltage conversion circuit as described in claim 2, characterized in that, If the modulation switch is not the control switch of the first sequence position, then the control switch corresponding to the previous sequence position of the modulation switch is always grounded.

4. The voltage conversion circuit as described in claim 2, characterized in that, Each of the level signals is either high or low. When the level signal is high, the second terminal of the corresponding control switch is connected to the preset reference voltage. When the level signal is low, the second terminal of the corresponding control switch is grounded.

5. The voltage conversion circuit as described in claim 1, characterized in that, The ratio of the resistance value of the first resistor to the resistance value of the second resistor is 1:

2.

6. The voltage conversion circuit as described in claim 1, characterized in that, The resistance value of the terminating resistor is the same as the resistance value of the second resistor.

7. The voltage conversion circuit as described in claim 1, characterized in that, The voltage conversion circuit further includes: A voltage regulator capacitor, wherein the first terminal of the voltage regulator capacitor is connected to the second terminal of the last first resistor, and the second terminal of the voltage regulator capacitor is grounded; A first incrementing resistor and a second incrementing resistor, wherein the first end of the first incrementing resistor is connected to the second end of the terminating resistor and the first end of the second incrementing resistor, respectively, and the second end of the first incrementing resistor is connected to the first end of the first resistor.

8. An electronic device, characterized in that, Includes the voltage conversion circuit as described in any one of claims 1 to 7.