DP83867IS: JTAG and other interface termination if not used

d_zero

Part Number: DP83867IS

Hi Team,

1) JTAG

What is the proper termination for JTAG of not used, considering the best performance in noisy environment?

As per DS JTAG_CLK, JTAG_TMS, JTAG_TDI have internal PU ( assuming 9k ) is that correct? What value do you suggest for external pull-up for better performance?

The JTAG_TDO output doesn't have nay PU or PD, what is the proper termination and value for the termination suggested ?

2) XO pin

When there is an oscillator used instead of crystal, what is the proper termination of the XO pin?

3) Unused LED pins

What is the proper termination of unused LED pins if they are not used and no strap resistor are connected to them?

Best Regards,

over 3 years ago

0 David Creger over 3 years ago

TI__Mastermind 28072 points

Hi D,

A few kohm PU will suffice (4.7kohm) for the input pins. Output pins are generally left floating to avoid unnecessary current draw.
XO "must be left floating if a clock oscillator is used" as stated in the datasheet.
4.7kohm to ground is fine.

Thanks,

David

0 d_zero over 3 years ago in reply to David Creger

Genius 5015 points

Hi David,

Should the unused LED pins also be configured as input? Is this possible to do via registers?

Br,

+1 David Creger over 3 years ago in reply to d_zero

TI__Mastermind 28072 points

Hi D,

My mistake. The LED pins are by default output pins, so please just leave them floating.

Thanks,

David

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DP83867IS: JTAG and other interface termination if not used