Hello,
I'm considering using the AMC3330 as a means to monitor a PTC thermistor in power semiconductor module and improve the isolation to my microprocessor at the same time.
I would want to use the isolated DC to drive a reference voltage chip and then feed PPTC and bias resistor load. My calculations suggest the PTC and bias resistor will draw about 0.54mA worst case and the reference would draw another 460uA worst case. Under these extreme conditions, it seems close to the spec for the DC/DC output for the chip, but that is an extreme in both cases. and the combo is more likely to be around 0.75mA.
Does this seem like a good idea?
The alternative is a separate DC/DC converter and iso amp etc.
regards
Steve
Hi Alexander, this is the circuit I'm proposing, by my calcs the combined ref, bias resistors and thermistor current draw is always below 1mA . The thermistor is mounted externally hence the zener protection. Any comments welcome.