OPA858: Part-to-part GBW Variation

Jejomar Ildefonso

Part Number: OPA858

Hi Team,

Our customer intends to design with our OPA858. But prior to this they'd like to know the minimum GBW to be expected when ordering multiple parts to have proper design margins. The typical GBW specification of OPA858 is given at 5.5GHz. What kind of part-to-part GBW variation can we expect on multiple OPA858? Is there a specific tolerance for GBW?

Thanks in advance!

Kind Regards,

Jejomar

over 3 years ago

0 Michael Steffes over 3 years ago

Guru 47395 points

Morning,

The 1st thing I Iook at is the supply current tolerances - does not look like this part has supply current trim, and, there is shift over temperature - both of these will spread out the statistics on GBP. To get real specific, you should probably ask your customer supply voltage tolerance and temp range.

My rule of thumb for untrimmed parts is +/-30% on GBP, but the product group has those specific simulations.

0 Hasan Babiker31 over 3 years ago

TI__Genius 15555 points

Hello Jejomar,

As Michael has mentioned, please help provide the temperature and supply conditions for the application.

Best,

Hasan Babiker

0 Jejomar Ildefonso over 3 years ago in reply to Hasan Babiker31

TI__Expert 8590 points

Hi Michael,

Thank you for sharing the helpful factors in considering GBP variations.

Hi Hasan,

Customer would be using +/-2.5V supply voltage at ~23°C to 35°C range.

Kind Regards,

Jejomar

0 Hasan Babiker31 over 3 years ago in reply to Jejomar Ildefonso

TI__Genius 15555 points

Hello Jejomar,

Thanks for the info. I will look into this and get back to you.

Best,

Hasan Babiker

0 Michael Steffes over 3 years ago in reply to Jejomar Ildefonso

Guru 47395 points

You bet, now keep in mind that if you are doing a transimpedance design, the GBP gets into the closed loop Fo as square root function - so +/-30% on the GBP is +/-15% on the closed loop Fo, It will of course vary the Q as well - about +/-15% also if the feedback RfCf is fixed,

0 Hasan Babiker31 over 3 years ago in reply to Michael Steffes

TI__Genius 15555 points

Hello Jejomar,

The response I got back from design is as follows:

The low limit on this specification is 4.6GHz. The data that was uploaded shows a range of 5.1GHz to 6.4GHz with 5.6GHz being nominal. I would expect the GBWP to be in that range most of the time but worst case, it could go down to 4.6GHz.

Best,

Hasan Babiker

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OPA858: Part-to-part GBW Variation