LP8867-Q1: Inquiry EVB Board (SNVU648) circuit

Charles Ko

Part Number: LP8867-Q1

Hi Team,

I have some question about LP8867-Q1 EVM Board (SNVU648) as below:
1. Does the function of FB2 (220ohm) & C17,C18,C19,C20(2200 pF) filter the harmonic of sw frequence 400K HZ??

or has other function??

2. For EVB board design, it use net to connect AGND & PGND,

Can it use 0 ohm resistor to connect AGND & PGND??

Or can only use single GND , not to divide AGND & PGND??

Thanks.

www.ti.com/.../snvu648.pdf

over 4 years ago

0 Charles-Chen over 4 years ago

TI__Genius 11836 points

Hi Charles,

1. It may help. The main target is to filter the noise at around MHz.

2.We recommend to do as the same as EVM board. But you can use 0 ohm to connect AGND and PGND.

0 Charles Ko over 4 years ago in reply to Charles-Chen

Prodigy 105 points

Hi Charles,

Thanks for your reply.

For the portion of ground , I would like to know the pros and cons for using single ground and two ground(PGND & AGND).

Could you help me??

0 Charles-Chen over 4 years ago in reply to Charles Ko

TI__Genius 11836 points

Hi Charles,

Two ground will be good to noise immunity.

Power management

Power management forum

LP8867-Q1: Inquiry EVB Board (SNVU648) circuit