OPA690: OPA690IDBVT substitute

Md Faisal Rahman

Part Number: OPA690

Hello

I was looking for OPA690IDBVT but can't find it anywhere. I have PCBs. Now I am looking for similar replacement to make: (1) inverting amplifier with gain =1, (2) non inverting amplifier with gain 2 and (3) a inverting summing amplifier. Please help.

Also, if I use other OP Amp with similar characteristics but with different Acl, min specific gain then will it cause any problem for the upper mentioned circuits? please let me know.

Thank you

Faisal

over 1 year ago

0 Michael Steffes over 1 year ago

Guru 47545 points

Hello Faisal,

The OPA690 is distinguished by having very high slew rate in a unity gain stable VFA, that comes with higher input noise.

Assuming the specifications were necessary, here are some close TI options to check out if they have SOT23-6 packaging, Disable feature is also a bit unique here.

There are similar parts industrywide, but I will sit on those for now,

0 Md Faisal Rahman over 1 year ago in reply to Michael Steffes

Prodigy 150 points

Hello Michael

Thank you for the suggestions. Can you also tell me what's the catch with ACL minimum specified value? Will it be a problem if I make an unity gain inverting amplifier with an OpAmp having minimun specified ACL of higher than 1?

Best

Faisal

0 kai klaas69 over 1 year ago in reply to Md Faisal Rahman

Guru 140200 points

Hi,

an inverting amplifier with a gain of -1V/V means a noise gain of 2V/V. So, your OPAmp needs a minimum stable gain of 2V/V. Best, you confirm by looking into the datasheet of OPAmp whether the manufacturer recommends the inverting amplifier with a gain of -1V/V.

Kai

0 Alec Saebeler over 1 year ago in reply to Md Faisal Rahman

TI__Genius 11585 points

Hello Faisal,

Please see this recent documentation regarding using decompensated op-amps in unity-gain configurations. If you have further questions or want to discuss a part you found to use instead of the OPA690 SOT23, please let me know.

https://www.ti.com/lit/an/sboa528/sboa528.pdf

Best,

Alec

Amplifiers

Amplifiers forum

OPA690: OPA690IDBVT substitute