AM5716: External resistor value for unused pins

user4936588

Prodigy 90 points

Part Number: AM5716

There is the following description in the specification of AM5716.

AE15 / AC15 / AE14 / D20 / AD17 / AC16 / V27 / AH25 / AE27 /AD27/Y28

These balls must be connected to GND through an external pull
resistor if unused

What is a good value for external pull resistor?

over 6 years ago

0 Biser Gatchev-XID over 6 years ago

TI__Guru**** 393215 points

It depends on the pin function. For DDR pins:

When not using all or part of a DDR interface, the proper method of handling the unused pins is to tie off the ddrx_dqsi pins to ground via a 1kΩ resistor and to tie off the ddrx_dqsni pins to the corresponding vdds_ddrx supply via a 1kΩ resistor. This needs to be done for each byte not used.

For other pins you can use the same or higher value (e.g. 4.7kΩ - 10kΩ).