TPS7A61-Q1: Recommended MIN ESR

Hidekazu Someno

Part Number: TPS7A61-Q1

Hi, team;

In TPS7A61xx-Q1 detasheet, the recommended minimum ESR of Cout has specified as 10mohms in Figure-13 & section-9.2.1.2.2.

However, most of ceramic capacitors(X5R/X7R, 10uF-47uF) have lower ESR than 10mohms.

How should we think about 10mohms of the recommended minimum ESR?

Can we judge that it is ok if minimum 10mohms is met in a special frequency range based on LDO's response characteristics?

Best regards,

Hidekazu Someno

over 8 years ago

0 Michael Hartshorne over 8 years ago

TI__Genius 13245 points

Someno-san,

I am checking with the team, but the TPS7A61 should be stable with any ceramic capacitor providing the capacitance is sufficient. I will confirm tomorrow.

Regards,
Mike

0 Hidekazu Someno over 8 years ago in reply to Michael Hartshorne

TI__Expert 5130 points

Mike-san,

Thanks for your reply.
Please tell me the result of your check.

Regards,
Hidekazu Someno

0 Michael Hartshorne over 8 years ago in reply to Hidekazu Someno

TI__Genius 13245 points

Hi Someno-san,

I verified that this device will work with any ceramic capacitor, provided the capacitance is high enough.

Regards,

Mike

0 Hidekazu Someno over 8 years ago in reply to Michael Hartshorne

TI__Expert 5130 points

Mike-san,

Thank you.

However, Customer requests us more clear cliteria.

How much is enough high capacitance? 10uF or Higherr?

How about capacitance <10uF?

Best regards,

Hidekazu Someno

0 Ryan Eslinger over 8 years ago in reply to Hidekazu Someno

TI__Guru 55940 points

Hi Someno-san,

The recommended output capacitor range for this device is 10 uF to 47 uF.

Very Respectfully,
Ryan

0 Hidekazu Someno over 8 years ago in reply to Ryan Eslinger

TI__Expert 5130 points

Ryan-san,

Thanks.

Now I understand that this part can have stable operation at any ceramic capactors(ESR<10mohms) in recommended Cout range(10uF-47uF).

Best regards,

Hidekazu Someno

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TPS7A61-Q1: Recommended MIN ESR