WEBENCH® Tools/TPS796: Output Impedance over frequency

Obinna Ezeilo

Part Number: TPS796

Tool/software: WEBENCH® Design Tools

Hi Team,

A customer of mine is trying to calculate the output impedance of the TPS796 regulator. An example Webench design has already been created: https://webench.ti.com/appinfo/webench/scripts/SDP.cgi?ID=CB0C85295DAD9FD4

As Webench allows only load transient simulation, getting a good plot of output impedance over frequency seems to be challenging. Can you kindly help out with a logarithmic plot of the output impedance vs. frequency of the Webench design in the above link?

Thanks and looking forward to your response.

Kind regards,

Obinna.

over 4 years ago

0 Bhushan Waghmare over 4 years ago

TI__Expert 3320 points

Hi Obinna,

Thanks for reporting this. Did we tried the exporting simulations in Webench? Let us know.

We should able to get back to you by early next week on this.

Best Regards

Bhushan

0 Obinna Ezeilo over 4 years ago in reply to Bhushan Waghmare

TI__Intellectual 2315 points

Hi Bhushan,

No I didn't try exporting the design. Would this help in getting the output impedance vs. frequency ?

Thanks and looking forward to your feedback early next week,

Regards,

Obinna.

0 Stephen Ziel over 4 years ago in reply to Obinna Ezeilo

TI__Mastermind 35845 points

Hi Obinna,

This spice model provides accurate typical steady state performance, but it is less accurate from the perspective of the output impedance of the linear regulator. Unfortunately this component does not have any output impedance plots in the datasheet. The output impedance is shaped by the internal feedback network of the LDO, but also your particular load impedance and load current. The best method to obtain this data is to use the EVM, apply your load, and take a measurement with your load.

The EVM can be found here:

http://www.ti.com/tool/TPS79601DRBEVM

Thanks,

- Stephen

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WEBENCH® Tools/TPS796: Output Impedance over frequency