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srob
- 22nd September 2005, 20:12
Trying to link a KMC-10 magnetic current sensor to a 16F73 ADC input, but also need a 0 to 10 volt aux output.

Because the sensor is a bridge (output in mV) am using a classic differential amplifier (1 op-amp, 4 resistors). To keep circuit simple decided to use a single ended op-amp, powered from a 7812 regulator.

Choosing the best op-amp proving a nightmare (no probs if I had a -12V rail), just unable to get the output to be 0V for no current I/P. So far had best results from a LM383, TLC271 and CA3160.

Wondered what amplifer others use for sensor signal conditioning?

CocaColaKid
- 22nd September 2005, 21:24
We are currently using Intersils CA3140E and CA3240E. Both parts seem to work really good. The only problem that we seen was if we did not have a 100 ohm resistor on the output and a small AC signal back fed it would smoke it. With the 100R resistor in series it works flawless. We on use 2 resistors in ours which seems to work pretty good.

mister_e
- 22nd September 2005, 21:32
google search gives me
http://cms.hlplanar.de/data-live-planar/docs/pdf/Datasheets_eng/KMC1_20.pdf

TL072 should work and it's very cheap