基于数字电位器的可编程电压基准源设计

在电子设计中为了灵活准确地设置电压基准值，设计了可编程电压基准源电路。详细阐述了电路的设计思路和工作原理。利用5片2.048 V带隙电压基准源芯片串联产生10.24 V电压作为基准。随后创新地利用单片机控制1024抽头的数字电位器对基准电压进行分压，结合精准运放的反向放大电路，最后输出-10.24 V到10.22 V的可编程精准电压值，输出电压分辨力达20 mV。测试结果表明，该电路具有输出线性度好、精度高、性能稳定等优点。

The Design of Programmable Voltage Reference Based on Digital Potentiometer

In order to set the value of voltage reference smartly and accurately in electronic design,a voltage reference circuit which output voltage can be programmed precisely is designed.The design idea and the working principle of the circuit are described in detail.Five 2.048 V bandgap type reference chips are connected in series, and output 10.24 V voltage as reference of other part of the circuit.And then a 1024-position digital potentiometer controlled by MCU is used to divide the 10.24 V reference voltage. Attributes to reverse amplifier circuit which uses high precision amplifier,the whole circuit can finally output accurate and programmable voltage from -10.24 V to 10.22 V.The output resolution can reach 20 mV.Test result shows that the circuit has the advantage of good linear output characteristics ,high precision and reliable performance.