OPA145: Alternative to OPA124

Hi Nishie-san,

Yuta Nishie said:

Since I am using it as a TIA, I am also concerned about the guard and shield.

The recommended OPA145's replacement is the following:

The op amp with the integrated shield guard is OPA928, but it may be overkill for your application. Could you tell us your TIA requirements? OPA320, OPA328, OPA32328 among others are great options for TIA application. Please let us know. 

Best,

Raymond

Hi Raymond-san,

I am sorry that I did not explain at the beginning. This time, I was wondering if you could tell me the replacement for OPA124 instead of OPA145. When I created the thread, I could not choose OPA124, so I chose OPA145.

Is the parts number you told me applicable to the replacement for OPA124?

Best Regards,

Nishie

Hi Nishie-san, 

There is no direct replacement for OPA124 BUT the closest would be OPA145, OPA191 and OPA196, or a lower supply voltage LMP7701 (max Vs<12V or +/-6V). --> this is copied from the previous thread.

I need to take a look at your TIA to decide what is the best replacement. For TIA application, the following op amp should work, but I am concerned about Ib current, unless Ib current errors can be substracted from TIA output in your application. The following TIA op amps can replace OPA124, unless the design has special requirements. In other words, I need to know the photodiode's characteristics, such as dark current,  input capacitance, impedance etc.. 

Here is the previous OPA124's datasheet. 

OPA124.pdf

Best,

Raymond

Hi Raymond-san,

Thank you for sharing the type name list.

I will tell the customer the type name you told me. I will also check the required specifications for TIA.

Best Regards,

Nishie

Hi Nishie-san, 

Yes, please let us know know the TIA requirements and this will help us to find the best op amp for the application. 

Best,

Raymond