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Topic: new to op amps, help with selecting the right one for the job (Read 1 time) previous topic - next topic

3z33

hello, can you please help me with recommendations for an op amp that will satisfy the following criteria?  I'm new to op amps, so please correct as needed:

1.  +Vss / -Vss can be supplied by the Arduino with no modifications (i believe this is 5V?)
2.  Input is simple two wire (+/-) that ranges between 0mv and 55mV
3.  Output needs to be suitable for an analog in on the Arduino (ideally 0v to 5v?, but any decent range in between works too)

Thanks.

elandd2011



Si

I keep coming back to the 7611.

http://www.intersil.com/data/fn/fn2919.pdf
Quote

• WideOperatingVoltageRange........... ±1Vto±8V
• HighInputImpedance ...................... 1012?
• Programmable Power Consumption . . . . . Low as 20?W
• InputCurrentLowerThanBIFETs...........1pA(Typ)
• OutputVoltageSwing ................... V+andV-
• InputCommonModeVoltageRangeGreaterThanSupply Rails (ICL7612)


Beat that for the price! I already know someone will ;)
--
My New Arduino Book: http://www.arduinobook.com

3z33

i did a google search for ICL7611 and they are $1.99?  does that sound right?

that's AWESOME, gonna give that a try.

Si

--
My New Arduino Book: http://www.arduinobook.com

jraskell

Quote
HighInputImpedance ...................... 1012?


I read that and thought, "Huh, did the definition of high input impedance change while I slept last night?"  Then I looked at the datasheet and saw that it was 1012? and realized it was just a copy/paste format error. 1 teraohms definitely qualifies as high input impedance.

Si

Quote
HighInputImpedance ...................... 1012?


Ah yes, 1012 would be an unusually precise (and low) input impedance.
--
My New Arduino Book: http://www.arduinobook.com

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