TPS2480: Questions of Layout

Penn Zhang

Part Number: TPS2480

There are some layout guide in datasheet, I have two questions:

1. Gate amplifier have hign bandwidth means can accept more noise, so need the trace short, is this right? or some other consideration.

2. The PROG TIMER EN pin have high input impedances, why these high impedences pin especially need the leads short, what's the consideration of short lead and high input impedances.

Thank you.

over 5 years ago

0 Rakesh over 5 years ago

TI__Guru** 105361 points

Hi Zhang,

1. Yes, you are right.

2. All the high input impedance pins should be routed short to avoid any coupling to the near by switching signals on the board

BR, Rakesh

0 Penn Zhang over 5 years ago in reply to Rakesh

TI__Intellectual 1180 points

Hi Rakesh,

Thank you for answering.

These input impedence means the impedence to GND or others?

Still confused why the high impedence pin are affected by coupling swiching signals easily?

Penn

0 Rakesh over 5 years ago in reply to Penn Zhang

TI__Guru** 105361 points

Hi Penn,

Because of high impedance, any small current injection due to coupling can lead to large voltage disturbance (Ismall * Rlarge) at that node

BR, Rakesh

0 Penn Zhang over 5 years ago in reply to Rakesh

TI__Intellectual 1180 points

Got you, thank you very much.

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TPS2480: Questions of Layout