DAC output circuit and electronic device
By combining digital-to-analog converter modules, resistor network modules, and switching modules, the DAC output circuit structure is simplified, enabling high-resolution analog output signal driving. This solves the problems of complexity and cumbersome control in existing DAC output circuits and improves the DAC's driving performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUZHOU HUAXING YUANCHUANG TECH CO LTD
- Filing Date
- 2025-08-04
- Publication Date
- 2026-07-21
AI Technical Summary
Existing DAC output circuits rely on complex multi-component combinations and cumbersome control methods, and need to be optimized to improve resolution.
By combining digital-to-analog converter modules, resistor network modules, and switching modules, high resolution of analog output signals is achieved through switching voltage divider nodes and conduction channels, simplifying the circuit structure and improving driving performance.
This invention achieves improved DAC output resolution with a simple circuit structure, enhances DAC driving performance, and reduces circuit complexity and control difficulty.
Smart Images
Figure CN224538186U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic circuit technology, and in particular to a DAC output circuit and electronic device. Background Technology
[0002] The digital-to-analog converter (DAC) output circuit is one of the core modules of a mixed-signal system. Its function is to convert the input digitally encoded signal into a continuous analog voltage or current signal. DACs are widely used in communication equipment (such as base station modems), high-precision industrial control (such as servo drives), audio processing (such as digital power amplifiers), and medical instruments (such as medical imaging). With the popularization of IoT and 5G technologies, systems have placed higher demands on the accuracy, dynamic range, and power consumption of DACs. Resolution, as a key performance indicator of a DAC, directly determines the fineness of the output signal and the overall system performance. DAC resolution refers to the smallest analog quantity change it can distinguish, usually expressed in bits. The higher the resolution (the more bits), the smaller the smallest difference that the analog output can distinguish, and the stronger the resolution capability. An n-bit DAC can distinguish 2ⁿ different input states and correspond to 2ⁿ different levels of analog output voltage. For example, a 12-bit DAC can provide 4096 output levels, while a 16-bit DAC increases this to 65536 levels. In applications, an 8-bit DAC with a full-scale voltage of 5V has a minimum output voltage step (LSB) of 5V / 2^8 ≈ 19.53mV, while the LSB of a 12-bit DAC can be reduced to 1.22mV. In DAC applications, increasing resolution has the following benefits: reduced quantization error (high-resolution DACs can reduce the stepped waveform distortion caused by digital quantization, significantly improving the signal-to-noise ratio (SNR), especially in audio and video applications); enhanced system dynamic range (in radar or communication systems, high-resolution DACs support a wider effective signal range, preventing small signals from being overwhelmed by noise); and simplified back-end filtering design (higher resolution allows for more relaxed roll-off requirements for anti-aliasing filters, reducing system complexity).
[0003] In related technologies, the resolution improvement of DAC output circuits mainly relies on two types of basic architectures: resistor / current-controlled DAC architecture and segmented architecture.
[0004] However, current DAC output circuits have the following technical problems:
[0005] Current DAC output circuits rely on complex circuit structures combining multiple components, and the control methods are cumbersome and need to be optimized. Utility Model Content
[0006] Therefore, it is necessary to provide a DAC output circuit and electronic device that can improve the resolution of the DAC output based on a simple circuit architecture.
[0007] This application provides a DAC output circuit, including:
[0008] A digital-to-analog converter module is used to convert digital input signals into analog output signals;
[0009] A resistor network module is connected to the digital-to-analog converter module. The resistor network module includes several voltage divider nodes. The resistor network module is used to receive the analog output signal and divide the analog output signal into voltages at the several voltage divider nodes.
[0010] A switching module is connected to the resistor network module. The switching module includes several conduction channels, each of which is connected to a voltage divider node in the resistor network module. The switching module is configured to receive control signals and switch different conduction channels according to the control signals. When the conduction channel is in the conduction state, it outputs the analog output signal after voltage division by the corresponding voltage divider node to the load.
[0011] In one embodiment, the resistor network module includes:
[0012] A series resistor network, comprising a plurality of interconnected voltage divider resistors, wherein the voltage divider nodes are located between adjacent voltage divider resistors, and the voltage divider nodes are also located between the digital-to-analog converter module and the series resistor network.
[0013] In one embodiment, the series resistor network has a first end and a second end, the first end of the series resistor network being coupled to the output of the digital-to-analog converter module, and the second end of the series resistor network being coupled to a reference ground.
[0014] In one embodiment, the switching module has an input side, an output side, and a control side. The input side includes a plurality of input terminals corresponding to the conduction channels. The input terminals of the switching module are coupled one-to-one with the voltage divider nodes of the resistor network module. The control side of the switching module is coupled to a control signal source. The output side of the switching module is coupled to the input terminal of the load.
[0015] In one embodiment, the control side of the switch module includes a plurality of control signal input terminals, which are used for control signals corresponding to a specific bit sequence. The switch module is configured to receive a plurality of bits of the control signals input by the control signal input terminals and control the target conduction channel to conduct based on the mapping relationship between the control signals and the conduction channel.
[0016] In one embodiment, the DAC output circuit further includes:
[0017] A first signal buffer module is located between the digital-to-analog converter module and the resistor network module to isolate the digital-to-analog converter module and the resistor network module.
[0018] In one embodiment, the first signal buffer module includes a first voltage follower having an input terminal and an output terminal. The input terminal of the first voltage follower is coupled to the output terminal of the digital-to-analog converter module, and the output terminal of the first voltage follower is coupled to the input terminal of the resistor network module.
[0019] In one embodiment, the DAC output circuit further includes:
[0020] The second signal buffer module is located between the switching module and the load, and is used to isolate the switching module from the load.
[0021] In one embodiment, the second signal buffer module includes a second voltage follower having an input terminal and an output terminal. The input terminal of the second voltage follower is coupled to the output terminal of the switching module, and the output terminal of the second voltage follower is coupled to the input terminal of the load.
[0022] Secondly, this application also provides an electronic device including a DAC output circuit according to any one of the first aspects.
[0023] The aforementioned DAC output circuit, derived from the technical features in the claims, can achieve the following beneficial effects in addressing the technical problems raised in the background art:
[0024] This application provides a DAC output circuit, including a digital-to-analog converter module, a resistor network module, and a switching module. The digital-to-analog converter module converts a digital input signal into an analog output signal. The resistor network module is connected to the digital-to-analog converter module and includes several voltage divider nodes. The resistor network module receives the analog output signal and divides the analog output signal into voltages at the voltage divider nodes. The switching module is connected to the resistor network module and includes several conduction channels. Each conduction channel is connected to one of the voltage divider nodes in the resistor network module. The switching module is configured to receive a control signal and switch different conduction channels according to the control signal. When a conduction channel is in the conducting state, it outputs the analog output signal divided by the corresponding voltage divider node to the load. In implementation, the digital-to-analog converter (DAC) can output analog signals based on its reference resolution, converting digital input signals into analog output signals. The analog output signals are then input to the resistor network module. Due to different voltage division ratios at each voltage divider node in the resistor network module, the analog output signals exhibit different voltage values at different voltage divider nodes. This achieves further subdivision of the analog output signals. By selecting voltage divider nodes through the switching module, the corresponding analog output signals after voltage division at the specified conduction channels are output. This enables the driving of the load with higher resolution analog output signals. Ultimately, a relatively simple circuit structure is used to improve the output resolution of a low-resolution DAC, enhancing the DAC's driving performance. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0026] Figure 1 This is a schematic diagram of the architecture of a DAC output circuit in an embodiment of this application;
[0027] Figure 2 This is a schematic diagram of another DAC output circuit architecture in an embodiment of this application;
[0028] Figure 3 This is a schematic diagram of the connection of a DAC output circuit in a specific embodiment of this application.
[0029] Explanation of reference numerals in the attached diagram: 100, digital-to-analog conversion module; 200, resistor network module; 300, switch module; 400, first signal buffer module; 500, second signal buffer module; 600, load. Detailed Implementation
[0030] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.
[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0032] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.
[0033] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.
[0034] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.
[0035] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.
[0036] This application was made by the inventor based on his understanding and research into the following issues:
[0037] In related technologies, the resolution improvement of DAC output circuits mainly relies on two types of basic architectures: resistor / current-controlled DAC architecture and segmented architecture.
[0038] However, current DAC output circuits have the following technical problems:
[0039] Current DAC output circuits rely on complex circuit structures combining multiple components, and the control methods are cumbersome and need to be optimized.
[0040] To address the aforementioned problems, this application provides a DAC output circuit. The DAC output circuit provided in this application can, as follows: Figure 1 As shown, it includes a digital-to-analog converter module, a resistor network module, and a switch module.
[0041] The digital-to-analog converter module is used to convert digital input signals into analog output signals.
[0042] The resistor network module is connected to the digital-to-analog converter module. The resistor network module includes several voltage divider nodes. The resistor network module is used to receive the analog output signal and divide the analog output signal into voltages at the several voltage divider nodes.
[0043] The switching module is connected to the resistor network module. The switching module includes several conduction channels, each of which is connected to a voltage divider node in the resistor network module. The switching module is configured to receive control signals and switch different conduction channels according to the control signals. When the conduction channel is in the conduction state, it outputs the analog output signal after voltage division by the corresponding voltage divider node to the load.
[0044] By implementing the DAC output circuit described above, the following beneficial effects can be achieved:
[0045] This application provides a DAC output circuit, including a digital-to-analog converter module, a resistor network module, and a switching module. The digital-to-analog converter module converts a digital input signal into an analog output signal. The resistor network module is connected to the digital-to-analog converter module and includes several voltage divider nodes. The resistor network module receives the analog output signal and divides the analog output signal into voltages at the voltage divider nodes. The switching module is connected to the resistor network module and includes several conduction channels. Each conduction channel is connected to one of the voltage divider nodes in the resistor network module. The switching module is configured to receive a control signal and switch different conduction channels according to the control signal. When a conduction channel is in the conducting state, it outputs the analog output signal divided by the corresponding voltage divider node to the load. In implementation, the digital-to-analog converter (DAC) can output analog signals based on its reference resolution, converting digital input signals into analog output signals. The analog output signals are then input to the resistor network module. Due to different voltage division ratios at each voltage divider node in the resistor network module, the analog output signals exhibit different voltage values at different voltage divider nodes. This achieves further subdivision of the analog output signals. By selecting voltage divider nodes through the switching module, the corresponding analog output signals after voltage division at the specified conduction channels are output. This enables the driving of the load with higher resolution analog output signals. Ultimately, a relatively simple circuit structure is used to improve the output resolution of a low-resolution DAC, enhancing the DAC's driving performance.
[0046] In one embodiment, the resistor network module includes:
[0047] A series resistor network, comprising a plurality of interconnected voltage divider resistors, wherein the voltage divider nodes are located between adjacent voltage divider resistors, and the voltage divider nodes are also located between the digital-to-analog converter module and the series resistor network.
[0048] In this embodiment, by setting up a series resistor network, a stepped voltage divider is achieved for the analog output signal, which helps to improve the flexibility and applicable scenarios of the DAC, while simplifying the circuit structure and reducing the configuration cost of the circuit.
[0049] For example, the series resistor network has a first end and a second end, the first end of the series resistor network being coupled to the output end of the digital-to-analog converter module, and the second end of the series resistor network being coupled to a reference ground.
[0050] In one embodiment, such as Figure 1 and Figure 3As shown, the switching module has an input side, an output side, and a control side. The input side includes several input terminals corresponding to the conduction channels. The input terminals of the switching module are coupled one-to-one with the voltage divider nodes of the resistor network module. The control side of the switching module is coupled to a control signal source. The output side of the switching module is coupled to the input terminal of the load.
[0051] In this embodiment, the voltage divider node is directly connected to the conduction channel, thereby enabling high-resolution output by changing the signal path through switching the conduction channel. This replaces the method of changing the resistor network topology, avoids transient noise caused by resistor recombination and other issues in traditional switched resistor AC circuits, and helps improve the stability of DAC output.
[0052] In one embodiment, the control side of the switch module includes a plurality of control signal input terminals, which are used for control signals corresponding to a specific bit sequence. The switch module is configured to receive a plurality of bits of the control signals input by the control signal input terminals and control the target conduction channel to conduct based on the mapping relationship between the control signals and the conduction channel.
[0053] For example, the mapping relationship between N-bit control signals and conduction channels can be determined based on binary encoding. For instance, four conduction channels can be controlled by 2-bit control signals, and eight conduction channels can be controlled by 3-bit control signals. The specific number of control signals and conduction channels can be determined by technicians according to actual application requirements.
[0054] For specific examples, such as Figure 3 As shown, the control signals A0 and A1 of the 4:1 analog switch select the conducting channel. When A0 and A1 are 00, 01, 10, and 11, they correspond to channels 1, 2, 3, and 4 of the switch module, respectively. In this case, channels 1-4 of the switch module are connected to the upper ends of resistors R1-R4, respectively. Switching between different ranges is achieved by switching the channels of the switch module, thereby improving the resolution of the analog output of the DAC. Taking channel 1 of the switch module as an example, connected to the upper end of resistor R1, the DAC output signal does not pass through the voltage divider of the resistor network module, so the output signal at the back end of the switch module has the same voltage as the DAC output signal. If channel 2 is selected, the output signal of the analog switch is: DAC output * (R2 + R3 + R4) / (R1 + R2 + R3 + R4).
[0055] In this embodiment, the switch module achieves multi-channel conduction control through a control signal input terminal with a relatively small number of bits, which helps to improve the flexibility of conduction control.
[0056] In one embodiment, it can be as follows Figure 2 and Figure 3 As shown, the DAC output circuit also includes:
[0057] A first signal buffer module is located between the digital-to-analog converter module and the resistor network module to isolate the digital-to-analog converter module and the resistor network module.
[0058] In this embodiment, by setting a first signal buffer module between the digital-to-analog conversion module and the resistor network module, it is helpful to isolate the DAC and the resistor divider network, thereby reducing the impact of the load effect of the resistor divider network on the DAC output accuracy and improving the driving performance of the circuit.
[0059] In one embodiment, the first signal buffer module includes a first voltage follower having an input terminal and an output terminal. The input terminal of the first voltage follower is coupled to the output terminal of the digital-to-analog converter module, and the output terminal of the first voltage follower is coupled to the input terminal of the resistor network module.
[0060] In one embodiment, it can be as follows Figure 2 and Figure 3 As shown, the DAC output circuit also includes:
[0061] The second signal buffer module is located between the switching module and the load, and is used to isolate the switching module from the load.
[0062] In this embodiment, by setting a second signal buffer module between the switching module and the load, it helps to isolate the switching module and the load, thereby reducing the impact of the switching module's on-resistance on the circuit output accuracy, reducing the possibility of signal attenuation, and helping to improve the circuit's driving performance.
[0063] In one embodiment, the second signal buffer module includes a second voltage follower having an input terminal and an output terminal. The input terminal of the second voltage follower is coupled to the output terminal of the switching module, and the output terminal of the second voltage follower is coupled to the input terminal of the load.
[0064] For specific examples, such as Figure 3As shown, taking a 10-bit DAC with a full-scale output of 2048mV as an example, the DAC's resolution is 2048 / 2^10 = 2mV. A series resistor network is formed using four resistors of the same value. The upper end of the four resistors is connected to the DAC's output, and the lower end is connected to GND. Each stage is connected to the input of the switching module. The switching module can be a 4:1 analog switch with four input channels and one output channel. Channels 1-4 are connected to the upper ends of voltage divider resistors R1-R4 respectively. In implementation, when channel 1 is selected as the input, the output is the same as the DAC's output, and the resolution is the same as the DAC chip's output resolution. When channel 2 is selected as the input, due to the voltage division of the resistors, the analog output is 2*3 / 4 = 1.5mV. Similarly, when channel 3 is selected as the input, the output is 1mV; when channel 4 is selected, the output is 0.5mV, thus improving the DAC's output accuracy. If the resolution of the analog signal directly output by the DAC is 1mV, then the DAC is 11 bits, 2048 / 2^11=1mV. If the resolution is 0.5mV, then the DAC needs to be 12 bits.
[0065] Based on the same inventive concept, this application also provides an electronic device, including a DAC output circuit according to any one of the above embodiments.
[0066] For a specific example, let's take a perovskite solar cell testing device as an example. Different test items require different voltage ranges, with significant voltage variations. For instance, there might be scenarios where a high-voltage output of 300V is needed, while a low-voltage output of 1mV is required. In this case, if a 16-bit DAC outputs an analog signal to control the voltage output within the 300V range, the minimum output voltage step would be 300V ÷ 65536 = 4.5mV, which is insufficient for the 1mV test requirement. However, by using the DAC output circuit within the device, the minimum analog signal can be reduced to one-quarter of its original size. The final output voltage then becomes 4.5mV ÷ 4 = 1.1mV, thus achieving the required resolution for the actual test.
[0067] It is understood that the DAC output circuit described above can also take other forms, and is not limited to the forms mentioned in the above embodiments, as long as it can achieve the function of improving the DAC output resolution.
[0068] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.
[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0070] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A DAC output circuit, characterized in that, include: A digital-to-analog converter module is used to convert digital input signals into analog output signals; A resistor network module is connected to the digital-to-analog converter module. The resistor network module includes several voltage divider nodes. The resistor network module is used to receive the analog output signal and divide the analog output signal into voltages at the several voltage divider nodes. A switching module is connected to the resistor network module. The switching module includes several conduction channels, each of which is connected to a voltage divider node in the resistor network module. The switching module is configured to receive control signals and switch different conduction channels according to the control signals. When the conduction channel is in the conduction state, it outputs the analog output signal after voltage division by the corresponding voltage divider node to the load.
2. The DAC output circuit according to claim 1, characterized in that, The resistor network module includes: A series resistor network, comprising a plurality of interconnected voltage divider resistors, wherein the voltage divider nodes are located between adjacent voltage divider resistors, and the voltage divider nodes are also located between the digital-to-analog converter module and the series resistor network.
3. The DAC output circuit according to claim 2, characterized in that, The series resistor network has a first end and a second end. The first end of the series resistor network is coupled to the output end of the digital-to-analog converter module, and the second end of the series resistor network is coupled to a reference ground.
4. A DAC output circuit according to claim 1, characterized in that: The switching module has an input side, an output side, and a control side. The input side includes several input terminals corresponding to the conduction channels. The input terminals of the switching module are coupled one-to-one with the voltage divider nodes of the resistor network module. The control side of the switching module is coupled to a control signal source. The output side of the switching module is coupled to the input terminal of the load.
5. A DAC output circuit according to claim 1, characterized in that, The control side of the switch module includes several control signal input terminals, which are used for control signals corresponding to different bit sequences. The switch module is configured to receive several bits of the control signals input by the control signal input terminals and control the target conduction channel to conduct based on the mapping relationship between the control signals and the conduction channel.
6. A DAC output circuit according to any one of claims 1 to 5, characterized in that, The DAC output circuit also includes: A first signal buffer module is located between the digital-to-analog converter module and the resistor network module to isolate the digital-to-analog converter module and the resistor network module.
7. A DAC output circuit according to claim 6, characterized in that, The first signal buffer module includes a first voltage follower, which has an input terminal and an output terminal. The input terminal of the first voltage follower is coupled to the output terminal of the digital-to-analog converter module, and the output terminal of the first voltage follower is coupled to the input terminal of the resistor network module.
8. A DAC output circuit according to any one of claims 1 to 5, characterized in that, The DAC output circuit also includes: The second signal buffer module is located between the switching module and the load, and is used to isolate the switching module from the load.
9. A DAC output circuit according to claim 8, characterized in that, The second signal buffer module includes a second voltage follower, which has an input terminal and an output terminal. The input terminal of the second voltage follower is coupled to the output terminal of the switching module, and the output terminal of the second voltage follower is coupled to the input terminal of the load.
10. An electronic device, characterized in that, Includes a DAC output circuit according to any one of claims 1-9.