What is the minimum driving strength (mA) for external driver to properly do reset configuration of the ColdFire/MCF54418CMJ250 (pins: BOOTMOD[1:0], FB_AD[7:0])? Thanks.

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What is the minimum driving strength (mA) for external driver to properly do reset configuration of the ColdFire/MCF54418CMJ250 (pins: BOOTMOD[1:0], FB_AD[7:0])? Thanks.

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davidwong
Contributor I

What is the minimum driving strength (mA) for external driver to properly do reset configuration of the ColdFire/MCF54418CMJ250 (pins: BOOTMOD[1:0], FB_AD[7:0])? Thanks.

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TomE
Specialist II

MCF54418 Data Sheet.

"Table 5. MCF5441x Signal information and muxing" shows BOOTMOD[1:0] and FB_AD[7:0] don't have pullups or pulldowns. FB_AD[15:8] do have Pulls on Reset though.

Section "Table 11. I/O electrical specifications" gives the "Input Leakage Current" for the pins.

If you look at the Reference Manuals, they usually say things like "The logic levels for reset configuration on FB_AD[7:0] must be actively driven when BOOTMOD equals 01". Then you check the Reference Designs and the Development Modules and find they often just use pullup or pulldown resistors on these pins. I've noted this here:

https://community.nxp.com/message/100980?commentID=100980#comment-100980

Tom

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