About pull-up/down resistance on TCK, MD0/MD1 pin

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Tao_2199
Level 3
Level 3
Distributor - TED (Japan)
25 replies posted 50 sign-ins First like given

Hello,

My customer is asking some questions about FM Family Hardware Design(AN203277)

1) According to document on page22, TCK pin is pulldown by external 10kΩ but TCK pin is pullup default by Pull-up Setting Register (PCRx).

In case of JTAG connection, does it need external 10kΩ pulldown resistor on TCK pin?

JTAG_TCK.png

 TCK_pullup.png

2) According to document on page24/25, 2kΩ external resistor are used for pull-up/down on MD0/MD1 pin.

And according to datasheet(S6E2H Series) on page58, it is described as following.

"Design the printed circuit board such that the pull-up/down resistance stays low, as well as the distance between the mode pins and VCC pins or VSS pins is as short as possible and the connection impedance is low,"

What is the recommended resistance value for pull-up/down on MD0/MD1 pin?  (2kΩ?)

 

Regards,

Tao_2199

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1 Solution
Takashi_M
Moderator
Moderator
Moderator
1000 replies posted 500 solutions authored 750 replies posted

Dear Tao_2199,

Apologize for our delay...

[Ans. 1] The external pull-down register is no "MUST".

[Ans. 2] 2kΩ would be recommended for pull up/down register on MD0/1 pins.

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3 Replies
Tao_2199
Level 3
Level 3
Distributor - TED (Japan)
25 replies posted 50 sign-ins First like given

Hello,

Would you  let me know current status about my question?

Regards,

Tao_2199

 

 

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Takashi_M
Moderator
Moderator
Moderator
1000 replies posted 500 solutions authored 750 replies posted

Dear Tao_2199,

Apologize for our delay...

[Ans. 1] The external pull-down register is no "MUST".

[Ans. 2] 2kΩ would be recommended for pull up/down register on MD0/1 pins.

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Tao_2199
Level 3
Level 3
Distributor - TED (Japan)
25 replies posted 50 sign-ins First like given

Hello TakashiM_61、

Thank you for reply.

I informed to my customer your answer.

My question will close.

Regards,
Tao2199

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