The present application relates to a kind of program-controlled resistance card and its program-controlled
resistor smooth control method, device, wherein the method includes obtaining the resistance card coding combination corresponding to current resistance value and target resistance value;Difference
mask is calculated by
exclusive or operation, and the
relay set to be changed is identified;Based on the strategy of
greedy algorithm, in the form of successive single-step switching, the
relay that makes instantaneous resistance value closest to target value is selected from the set identified by difference
mask and is operated;Switching and state updating are iteratively executed until difference
mask is zero;Finally, switching completion
signal is output.The device includes state acquisition,
difference analysis, switching decision and driving execution module, and through the orderly single-step
relay switching control, smooth transition in the resistance value change process is realized, the extreme state such as open circuit or
short circuit is effectively avoided, the switching precision and
system reliability are significantly improved, and it is suitable for precision
test measurement and
automation control field.