BQ25882: Capacitance value for PMID.

Kengo.Y

Part Number: BQ25882

Hi team,

Could you tell me about the capacitance value for PMID?

According to the datasheet, it wrote the capacitance is typ 10uF.

My customer wants to use 22uF for PMIDpin.
Because 10uF is insufficient for the output load response.

Sincerely.
Kengo.

over 4 years ago

0 Ricardo over 4 years ago

TI__Genius 10385 points

Kengo-san,

Your customer may use 22uF. I have attached a schematic checklist to help guide them through component selections.

I hope this resolves your issue,

Ricardo

0207.BQ2588x_SchematicChecklist_AddPCBcomment.pdf

0 Kengo.Y over 4 years ago in reply to Ricardo

Guru 10735 points

Ricardo-san,

Thank you for your reply.
Could you tell me one more question?

According to your att file, the additional capacitor of PMIDpin is for inrush current.

I want to ask you about this inrush current.
Do you have the assumed resistance value of a high impedance cable?
Or is there an estimated inrush current?

Sincerely.
Kengo.

0 Ricardo over 4 years ago in reply to Kengo.Y

TI__Genius 10385 points

Kengo-san,

There is no assumed impedance value for the adapter cable or inrush current value, but you should strive to minimize the impedance by using short, high quality adapter cables.

I hope this resolves your issue,

RIcardo

0 Kengo.Y over 4 years ago in reply to Ricardo

Guru 10735 points

Hi Ricardo,

Thank you for your reply.

Why did you recommend 30uF for PMID?
My customer want to know the basis of this.

Sincerely.
Kengo.

0 Ricardo over 4 years ago in reply to Kengo.Y

TI__Genius 10385 points

Kengo-san,

30uF (Recommended) + 10uF (Required) + 10nF (Optional) = 40.01 uF.

40.01 uF is the maximum capacitance value recommended by the designer. Excess capacitance on PMID can slow the PMID rise time and result in problems upon power up.

I hope this resolves your issue,

Ricardo

Power management

Power management forum

BQ25882: Capacitance value for PMID.