Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

  • State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 47 subscribers
  • Views 821 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

OPA2107 Unusual high DC offset at the output.

li wang101153
Prodigy 90 points
Other Parts Discussed in Thread: OPA2107, OPA2132, TINA-TI

Hello,

         I have an audio circuit that use a standard dual input operational amplifier. I tried different opamps and when I inserted opa2132, the DC voltage at the output is around 5mw. However, when I switch the OPAMP to Difet OPA2107, the DC offset at the output went up to 250mw. Can someone tell me how to solve this issue?

  • 0
    TI__Genius 13335 points

    Hello,

    From the description and the picture, there are a couple things that are unclear. Is R5 = 0Ω? Is the symbol above the NPN transistors V+? What voltage supplies are you using? When you say output has a DC voltage, are you referring to the output of the amplifier or the output after the feedback path? Also, by 250mW I assume you mean 250mV, correct?

    I've attached a TINA-TI simulation of your circuit with both the OPA2132 and the OPA2107 included. Both circuits appear to be functioning the same and there don't seem to be any large offsets present.

    1018.OPA2107 - OP2132 Comparison.TSC

    Regards,
    Luke Lapointe
    High Speed Amplifiers