An app note from ON Semiconductors.
The digital POT has two temperature dependent parameters, the TC of the end-to-end resistance RPOT and the ratiometric TC. The temperature dependence of the parameters of an analog circuit using a digital POT is reduced if the performance of the circuit is shifted from the TC of the end-to-end resistance of the pot to the ratiometric TC.
The temperature dependence of electronic products can be reduced using a number of different approaches. One approach, for those products where it is possible, is to use a closed-loop, feedback system to calibrate the product’s electronics before any measurement or signal processing activity is initiated. The calibration procedure can correct for any internal changes due to temperature or other environmental factors. A second approach is to use low temperature dependent components at the circuits’ level.
A third approach is to use a circuit topology whose performance with temperature is shifted from high TC parameters to low TC parameters.