single supply DC amplifier

[jmantilla]

For a PIC temperature metter/logger I need to amplify (x10) the output signal from a LM35 IC.

Which might be an easy to find single supply OpAmp, low voltage (running on batteries) to handle about 200mV from ground as input ?

Other ideas to capture such small signals with PIC's ADC ?

 

[John Sorensen]

Look at "instrument amps." Burr-Brown's INA122 is one.

j.

 

[Optikon]

For a PIC temperature metter/logger I need to amplify (x10) the output signal from a LM35 IC.

Which might be an easy to find single supply OpAmp, low voltage (running on batteries) to handle about 200mV from ground as input ?

Other ideas to capture such small signals with PIC's ADC ?

Find a rail-to-rail input opamp these can accept input voltages very close if not equal to supply rails.

You could also use a low cost mainstream opamp like 741 and bias the whole measurement circuit off of ground. but extra components necessary will likely offset the extra cost of a r2r or inamp anyhow.. but its another way. Look at LM3 schematic, you might be able to bias it off of ground so its lowest output is within range of your amp..