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Design >> Analog Design >> Op-amp comparison (op07-TLE2027-op177)?????
https://designers-guide.org/forum/YaBB.pl?num=1292108531

Message started by Sonnet on Dec 11^th, 2010, 3:02pm

Title: Op-amp comparison (op07-TLE2027-op177)?????
Post by Sonnet on Dec 11^th, 2010, 3:02pm

Dear all
Hi, I've used op- amps "TLE2027", and "op07" in my design to make a frequency selective amplifier with gain of 30 dB and BW of 20HZ (0.05-20 Hz). During tests I found out TLE2027 have no response to my design so I've replaced it with OP07 and it immediately worked. On the other hand at first I've considered working with op177 but as I need to have POSITIVE supply voltage (+5 and GND) I changed the design and considered TLE2027 & OP07.
Now the thing is my circuit it working, but I've no idea why!! because I've been told by technician to use them,and when I asked him the reason he just knows it through his experience.
I'm reading their datasheets now, but they are not helpful.
Any idea would be appreciated :-[

Title: Re: Op-amp comparison (op07-TLE2027-op177)?????
Post by sheldon on Dec 11^th, 2010, 8:58pm

Sonnet,

Looking at the data sheets, the TLE-2027 is only specified down to
8V, +/-4V. Looked at the AD, Maxim, Linear Tech, National, and TI
data sheets for the OP-07. National and TI had a minimum supply
voltage listed for the OP-07 and it was 6V. So the manufacturer states
that the minimum voltage for the TLE-2027 is 8V, +/-4V, and this may
explain the issues you are experiencing. You might want to see how
much margin your design has since the OP-07 is only specified to
+/-3V.

Best Regards,

Sheldon

Title: Re: Op-amp comparison (op07-TLE2027-op177)?????
Post by Sonnet on Dec 11^th, 2010, 9:08pm

Dear Sheldon
Thank you so much for taking look at all those datasheets, I'm reading a book now which said TLE2027 can only swing 2v of its supply voltages, so if supply is 8v as you said, I can't expecting it to give me 5v.
Thanks again
Sonnet :)