I recently started testing my ADN8831-EVALZ board for its heating and cooling control ability.I am currently using a 10k NTC thermistor. I can successfully heat the target device. However, when I try to cool the device to a temperature of 5 degrees celsius, the TEC current decreases slowly, but the target temperature increases similarly. Also, the TEC current polarity does not reverse.
Can anyone give suggestions to get a cooling current?