Digital-to-analog conversion circuit and electronic device

Abstract

The utility model provides a digital-to-analog conversion circuit and electronic equipment, and relates to the technical field of digital-to-analog conversion circuits. In the digital-to-analog conversion circuit, a voltage source module is connected with a voltage division module and is used for providing a voltage signal for voltage division for the voltage division module; the voltage dividing module comprises a digital potentiometer, the input end of the digital potentiometer is connected with the voltage source module, and the voltage dividing module is connected with a signal sending object sending the digital signals and used for adjusting internal resistance of the digital potentiometer according to the received digital signals so as to output voltage dividing signals corresponding to the digital signals. According to the embodiment of the invention, accurate conversion between the digital signal and the analog signal can be realized through the characteristics of the digital potentiometer and precision control logic, the precision of digital-to-analog conversion is ensured, the cost of the digital-to-analog conversion circuit is effectively reduced, and the reliability is good.

Description

Technical Field

[0001] The present application relates to the technical field of digital-to-analog conversion, and in particular to a digital-to-analog conversion circuit and an electronic device. Background Art

[0002] As a bridge between digital and analog signals, the digital-to-analog converter (DAC) circuit plays a vital role in modern electronic devices. Its application areas extend from high-fidelity audio systems to all aspects of industrial automation control. It is widely used in various electronic devices used in people's daily lives.

[0003] In the prior art, digital-to-analog conversion circuits often use specific digital-to-analog conversion chips to convert digital signals into analog signals. However, digital-to-analog conversion chips are expensive and easily affected by external electrical signal fluctuations, resulting in poor reliability. Utility Model Content

[0004] The embodiments of the present application provide a digital-to-analog conversion circuit and an electronic device, which can solve the problems of high cost and poor reliability of existing digital-to-analog conversion circuits.

[0005] To achieve this goal, the embodiments of the present application provide the following solutions.

[0006] According to one aspect of an embodiment of the present application, a digital-to-analog conversion circuit is provided, comprising a voltage source module and a voltage divider module, wherein the voltage source module is connected to the voltage divider module and is configured to provide a voltage signal for voltage division to the voltage divider module;

[0007] The voltage divider module includes a digital potentiometer, the input end of the digital potentiometer is connected to the voltage source module, and the voltage divider module is connected to a signal sending object that sends a digital signal, and is used to adjust the internal resistance of the digital potentiometer according to the received digital signal to output a voltage divider signal corresponding to the digital signal.

[0008] In one possible implementation, the voltage source module includes a voltage reference circuit and an amplifier circuit, the voltage reference circuit is connected to the power supply, and the output end of the voltage reference circuit is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the voltage divider module.

[0009] In one possible implementation, the voltage reference circuit includes a voltage reference chip, a first resistor and a first capacitor, the first end of the voltage reference chip is connected to the second end of the first resistor, the first end of the first capacitor, the third end of the voltage reference chip and the amplifier circuit, the second end of the voltage reference chip is grounded, the first end of the first resistor is connected to the power supply, and the second end of the first capacitor is grounded.

[0010] In one possible implementation, the amplification circuit includes a first operational amplifier, a second resistor, and a third resistor, the non-inverting input terminal of the first operational amplifier is connected to the voltage reference circuit, the first end of the third resistor is connected to the inverting input terminal of the first operational amplifier and the second end of the second resistor, the second end of the third resistor is grounded, and the first end of the second resistor is connected to the output terminal of the first operational amplifier.

[0011] In one possible implementation, the voltage divider module further includes a fourth resistor and a fifth resistor, the first end of the fourth resistor is connected to the voltage source module, the second end of the fourth resistor is connected to the input end of the digital potentiometer, the first end of the fifth resistor is grounded, the second end is connected to the digital potentiometer, and the signal receiving end of the digital potentiometer is connected to the signal sending object.

[0012] In a possible implementation, a voltage follower circuit is further included, and the voltage follower circuit is connected to the voltage division signal output terminal of the digital potentiometer.

[0013] In one possible implementation, the voltage follower circuit includes a second operational amplifier and a first connector, the non-inverting input terminal of the second operational amplifier is connected to the voltage divider signal output terminal of the digital potentiometer, and the inverting input terminal is connected to the output terminal of the second operational amplifier and the first connector.

[0014] According to one aspect of an embodiment of the present application, an electronic device is provided, comprising the digital-to-analog conversion circuit as described above.

[0015] In a possible implementation, the signal sending object includes a single-chip microcomputer, and the single-chip microcomputer is connected to the digital potentiometer of the voltage divider module to send a digital signal to the digital potentiometer.

[0016] The beneficial effects of the technical solution provided by the embodiments of the present application are:

[0017] In the digital-to-analog conversion circuit provided by the present application, a voltage source module is connected to a voltage divider module for providing a voltage signal for voltage division to the voltage divider module; the voltage divider module includes a digital potentiometer, the input end of the digital potentiometer is connected to the voltage source module, and the voltage divider module is connected to a signal transmission object that transmits a digital signal, and is used to adjust the internal resistance of the digital potentiometer according to the received digital signal to output a voltage divider signal corresponding to the digital signal. The embodiments of the present application can achieve accurate conversion of digital signals and analog signals through the characteristics of the digital potentiometer and precise control logic, ensure the accuracy of digital-to-analog conversion, effectively reduce the cost of the digital-to-analog conversion circuit, and have good reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings required for describing the embodiments of the present application.

[0019] Figure 1 A structural diagram of a digital-to-analog conversion circuit provided in an embodiment of the present application;

[0020] Figure 2 A circuit diagram of a digital-to-analog conversion circuit provided in an embodiment of the present application;

[0021] Figure 3 A flowchart of the digital-to-analog conversion circuit provided in an embodiment of the present application;

[0022] Figure 4 This is a structural diagram of an electronic device provided in an embodiment of the present application.

[0023] Explanation of reference symbols: U1, digital potentiometer; U4, voltage reference chip; R1, first resistor; C1, first capacitor; U2, first operational amplifier; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; U3, second operational amplifier; J1, first connector. DETAILED DESCRIPTION

[0024] The following describes the embodiments of the present application in conjunction with the accompanying drawings. It should be understood that the embodiments described below in conjunction with the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions of the embodiments of the present application.

[0025] Those skilled in the art will understand that, unless otherwise stated, the singular forms "a," "an," "said," and "the" used herein may also include plural forms. It should be further understood that the terms "including" and "comprising" used in the embodiments of the present application mean that the corresponding features can be implemented as the presented features, information, data, steps, operations, elements, and / or components, but do not exclude implementation as other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by the present technical field. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, the element can be directly connected or coupled to the other element, or it can refer to the element and the other element establishing a connection relationship through an intermediate element. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The term "and / or" used herein indicates at least one of the items defined by the term, for example, "A and / or B" indicates implementation as "A," or implementation as "A," or implementation as "A and B."

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0027] The following describes several exemplary embodiments to illustrate the technical solutions of the embodiments of the present invention and the technical effects produced by the technical solutions of the present invention. It should be noted that the following embodiments can refer to, draw on, or combine with each other, and the same terms, similar features, and similar implementation steps in different embodiments will not be repeated.

[0028] The digital-to-analog conversion circuit and electronic device provided in this application are intended to solve at least one technical problem existing in the prior art.

[0029] In an embodiment of the present application, a digital-to-analog conversion circuit is provided, such as Figure 1-Figure 3 As shown, the digital-to-analog conversion circuit includes a voltage source module and a voltage divider module. The voltage source module is connected to the voltage divider module and is used to provide a voltage signal for voltage division to the voltage divider module; the voltage divider module includes a digital potentiometer U1, the input end of the digital potentiometer U1 is connected to the voltage source module, and the voltage divider module is connected to a signal sending object that sends a digital signal, and is used to adjust the internal resistance of the digital potentiometer U1 according to the received digital signal to output a voltage divider signal corresponding to the digital signal.

[0030] Optionally, digital potentiometer U1, as a programmable resistor, can precisely adjust its internal resistance under digital control, thereby achieving fine control of analog signals. Specifically, digital potentiometer U1 outputs a voltage-dividing signal through a voltage-dividing signal output terminal. The object transmitting the digital signal can be a single-chip microcomputer. Digital potentiometer U1 adjusts the resistance between the input terminal and the voltage-dividing signal output terminal based on the received digital signal, thereby changing the voltage of the voltage-dividing signal at the output terminal to match the digital signal.

[0031] In one embodiment, the digital potentiometer U1 may be a CAT5172TBI-50GT3 with 256 taps and 8-bit precision. The voltage source module may provide a 2.5V voltage signal to the digital potentiometer U1. The digital potentiometer U1 communicates with a signal sending object via the SPI protocol. The signal sending object assigns values ​​to registers within the digital potentiometer U1, and the digital potentiometer U1 adjusts its internal resistance based on the assigned values.

[0032] Optionally, the voltage source module includes a voltage reference circuit and an amplifier circuit, the voltage reference circuit is connected to the power supply, and the output end of the voltage reference circuit is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the voltage divider module.

[0033] Optionally, the power supply may also be connected to the amplifier circuit and the digital potentiometer U1 to supply power to the amplifier circuit and the digital potentiometer U1.

[0034] In one embodiment, the power supply may provide direct current, and the voltage thereof may be 3V-5.5V.

[0035] Optionally, the voltage reference circuit includes a voltage reference chip U4, a first resistor R1, and a first capacitor C1. A first end of the voltage reference chip U4 is connected to the second end of the first resistor R1, the first end of the first capacitor C1, a third end of the voltage reference chip U4, and the amplifier circuit. A second end of the voltage reference chip U4 is grounded. A first end of the first resistor R1 is connected to a power supply, and a second end of the first capacitor C1 is grounded. The voltage reference circuit provides a high-precision DC voltage signal.

[0036] In one embodiment, the model of the voltage reference chip U4 may be TL431G-AB3-R. The operating voltage of the voltage reference chip U4 is 2.5V-36V, and it provides a 2.5V high-precision voltage signal.

[0037] Optionally, the amplifier circuit is a non-inverting amplifier circuit, wherein the amplifier circuit includes a first operational amplifier U2, a second resistor R2 and a third resistor R3, the non-inverting input terminal of the first operational amplifier U2 is connected to the voltage reference circuit, the first end of the third resistor R3 is connected to the inverting input terminal of the first operational amplifier U2 and the second end of the second resistor R2, the second end of the third resistor R3 is grounded, and the first end of the second resistor R2 is connected to the output terminal of the first operational amplifier U2.

[0038] Optionally, the voltage terminal of the first operational amplifier U2 is connected to the power supply, and the ground terminal is grounded. The amplification factor of the amplifier circuit is 1+the resistance value of the second resistor R2 / the resistance value of the third resistor R3.

[0039] In one embodiment, the model of the first operational amplifier U2 may be LM358S_C408270.

[0040] Optionally, the voltage divider module also includes a fourth resistor R4 and a fifth resistor R5, the first end of the fourth resistor R4 is connected to the voltage source module, the second end of the fourth resistor R4 is connected to the input end of the digital potentiometer U1, the first end of the fifth resistor R5 is grounded, the second end is connected to the digital potentiometer U1, and the signal receiving end of the digital potentiometer U1 is connected to the signal sending object.

[0041] In one embodiment, the seventh pin of the digital potentiometer U1 is connected to the second end of the fifth resistor R5, and the fourth pin, the fifth pin, and the sixth pin of the digital potentiometer U1 are connected to the signal transmission object. The power supply supplies power to the digital potentiometer U1 through the second pin of the digital potentiometer U1. The voltage U of the voltage-divided signal output by the digital potentiometer U1 is 分压 =U 运放输出电压 *(resistance of the fifth resistor R5 + R 数字电位计设置值 ) / (R 数字电位计总阻值 + the resistance of the fourth resistor R4 + the resistance of the fifth resistor R5). Wherein, U 运放输出电压 is the voltage of the electrical signal output by the amplifier circuit, R 数字电位计设置值 R is the resistance value of the resistor used to generate the voltage divider signal set inside the digital potentiometer U1 according to the digital signal. 数字电位计总阻值 is the total resistance of digital potentiometer U1.

[0042] Optionally, the digital-to-analog conversion circuit may further include a voltage follower circuit connected to the voltage-dividing signal output terminal of the digital potentiometer U1 , thereby improving the stability and load capacity of the voltage-dividing signal.

[0043] Optionally, the voltage follower circuit includes a second operational amplifier U3 and a first connector J1, the non-inverting input terminal of the second operational amplifier U3 is connected to the voltage divider signal output terminal of the digital potentiometer U1, and the inverting input terminal is connected to the output terminal of the second operational amplifier U3 and the first connector J1.

[0044] In one embodiment, the model of the second operational amplifier U3 may be LM358S_C408270, and the model of the first connector J1 may be HDR-M-2.54_1x1.

[0045] The following further describes the digital-to-analog conversion circuit through its working process.

[0046] Alternatively, as Figure 3 As shown, the voltage reference chip U4 in the voltage reference circuit provides a precise input reference voltage to the amplifier circuit. The amplifier circuit adjusts the amplitude of the input reference voltage to achieve signal amplification. The digital potentiometer U1 in the voltage divider module divides the voltage output of the amplifier circuit by adjusting its resistance value, and the voltage follower circuit improves the load capacity of the voltage divider output.

[0047] The embodiment of the present application utilizes common voltage reference chips, operational amplifiers, digital potentiometers, capacitors and resistors to build a digital-to-analog conversion circuit. While achieving accurate conversion between digital signals and analog signals through the characteristics of the digital potentiometer and precise control logic, it can not only ensure the accuracy of the digital-to-analog conversion, but also effectively reduce the cost of the digital-to-analog conversion circuit and have good reliability.

[0048] According to one aspect of the embodiments of the present application, an electronic device is also provided, such as Figure 4 As shown, the electronic device includes the digital-to-analog conversion circuit as described in the above embodiment.

[0049] Optionally, the signal sending object connected to the digital-to-analog conversion circuit includes a single-chip microcomputer, and the single-chip microcomputer is connected to the digital potentiometer of the voltage divider module to send a digital signal to the digital potentiometer.

[0050] The terms "first," "second," "third," "fourth," "1," "2," and the like (if any) in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or sequential sequence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the application described herein can be implemented in an order other than that shown or described in the drawings.

[0051] It should be understood that, although each operation step is indicated by arrows in the flowchart of the embodiment of the present application, the order of implementation of these steps is not limited to the order indicated by the arrows. Unless otherwise clearly stated herein, in some implementation scenarios of the embodiment of the present application, the implementation steps in each flowchart can be performed in other orders according to demand. In addition, some or all of the steps in each flowchart can include multiple sub-steps or multiple stages based on actual implementation scenarios. Some or all of these sub-steps or stages can be executed at the same time, and each sub-step or stage in these sub-steps or stages can also be executed at different times respectively. Under different scenarios at the execution time, the execution order of these sub-steps or stages can be flexibly configured according to demand, and the embodiment of the present application does not limit this.

[0052] The above description is only an optional implementation method for some implementation scenarios of this application. It should be pointed out that for ordinary technicians in this technical field, without departing from the technical concept of the solution of this application, the use of other similar implementation methods based on the technical ideas of this application also falls within the protection scope of the embodiments of this application.

Claims

1. A digital-to-analog conversion circuit, characterized in that: It includes a voltage source module and a voltage dividing module, wherein the voltage source module is connected to the voltage dividing module and is used to provide a voltage signal for voltage division to the voltage dividing module; The voltage divider module includes a digital potentiometer, the input end of the digital potentiometer is connected to the voltage source module, and the voltage divider module is connected to a signal sending object that sends a digital signal, and is used to adjust the internal resistance of the digital potentiometer according to the received digital signal to output a voltage divider signal corresponding to the digital signal.

2. The digital-to-analog conversion circuit according to claim 1, wherein: The voltage source module includes a voltage reference circuit and an amplifier circuit. The voltage reference circuit is connected to a power supply, and the output end of the voltage reference circuit is connected to the input end of the amplifier circuit. The output end of the amplifier circuit is connected to the voltage divider module.

3. The digital-to-analog conversion circuit according to claim 2, wherein: The voltage reference circuit includes a voltage reference chip, a first resistor and a first capacitor. The first end of the voltage reference chip is connected to the second end of the first resistor, the first end of the first capacitor, the third end of the voltage reference chip and the amplifier circuit. The second end of the voltage reference chip is grounded, the first end of the first resistor is connected to the power supply, and the second end of the first capacitor is grounded.

4. The digital-to-analog conversion circuit according to claim 2, wherein: The amplifier circuit includes a first operational amplifier, a second resistor and a third resistor. The non-inverting input terminal of the first operational amplifier is connected to the voltage reference circuit, the first end of the third resistor is connected to the inverting input terminal of the first operational amplifier and the second end of the second resistor, the second end of the third resistor is grounded, and the first end of the second resistor is connected to the output terminal of the first operational amplifier.

5. The digital-to-analog conversion circuit according to claim 1, wherein: The voltage divider module also includes a fourth resistor and a fifth resistor. The first end of the fourth resistor is connected to the voltage source module, and the second end of the fourth resistor is connected to the input end of the digital potentiometer. The first end of the fifth resistor is grounded, and the second end is connected to the digital potentiometer. The signal receiving end of the digital potentiometer is connected to the signal sending object.

6. The digital-to-analog conversion circuit according to claim 1, wherein: It also includes a voltage follower circuit, which is connected to the voltage-dividing signal output terminal of the digital potentiometer.

7. The digital-to-analog conversion circuit according to claim 6, wherein: The voltage follower circuit includes a second operational amplifier and a first connector. The non-inverting input terminal of the second operational amplifier is connected to the voltage divider signal output terminal of the digital potentiometer, and the inverting input terminal is connected to the output terminal of the second operational amplifier and the first connector.

8. An electronic device, characterized in that: The electronic device comprises the digital-to-analog conversion circuit according to any one of claims 1 to 7.

9. The electronic device according to claim 8, wherein: The signal sending object includes a single chip microcomputer, and the single chip microcomputer is connected to the digital potentiometer of the voltage divider module to send a digital signal to the digital potentiometer.

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