• Not Answered

LM57 V(TEMP) Design Considerations

I would like to design a simple board which controls a resistor as a heater. At T(1), heater (resistor) will be ON and at T(2), heater will be OFF and T(1)<T(2).

I can set the R(SENSE) and hysteresis values and if i do so, I understand that my output voltage V(TEMP) is about 1V so it is not suitable to heat a 150k resistor for example.

Can I increase the output voltage V(TEMP) via an op-amp and what possible errors will occur on hysteresis or on temperature sensing if I do so? Is there another way of doing this board via another product?

It says LM57 uses NTC for V(TEMP) in datasheet. Does this mean I can not control the heater as temperature is inversely proportional to V(TEMP) output so that as temperature decreases, voltage on V(TEMP) is increased?


3 Replies