Both mechanical potentiometers and digital potentiometers have uncertain end-to-end tolerances. General digital potentiometers have an error of 20% to 30%. I have seen on the Internet that proportional circuit circuits can eliminate this error, please ask What is the principle?
Nayeli Posted on August 6, 2020
The resistance deviation is converted into an acceptable current change, which can effectively eliminate the voltage change.
Itzel Posted on August 6, 2020
You can refer to this circuit:
Skyla Posted on August 6, 2020
The immediate problem faced by this design is that a 3% error can cause the voltage to vary between 3V and 4.5V. Use the block diagram shown in Figure 1 to perform basic calculations. The digital potentiometer is 50kΩ (25% tolerance), R1 is 16.5K (1%), and R2 is 100K (1%). The 25% tolerance of the potentiometer's end-to-end resistance is the largest source of error in the design.
