LPCXpresso IDEのトピックLPC11C14 port pull-up resistor value ?

LPC11C14 port pull-up resistor value ?

lpcware — Thu, 16 Jun 2016 02:55:32 GMT

Content originally posted in LPCWare by DaveNadler on Sat Feb 18 15:30:06 MST 2012
[FONT=Arial]Sorry if I'm being dense, but I cannot find the range of values for the built-in pull-up or pull-down resistors on GPIO ports. All the diagrams (user manual and datasheet) just say "weak". I need to know the actual range of values.
Thanks in advance, Best Regards, Dave

PS: This to ensure external ESD-suppression components are sized such that the port still works as an input...

PPS: Input current graph seems to imply min 50ua for Vin < 1v, or equivalent of ~66k for 3.3v supply ? Is this the only spec ? Graph is "Fig 16. Typical pull-up current Ipu versus input voltage VI"
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Re: LPC11C14 port pull-up resistor value ?

lpcware — Thu, 16 Jun 2016 02:55:33 GMT

Content originally posted in LPCWare by js-nxp on Sat Feb 18 19:17:23 MST 2012
The internal "weak" resistors are usually in the range of 30K-100K with [B]OTHER[/B] micros I work with.

I would suggest that you turn off the resistors if you have external ESD or other networks which can keep the pin at the require quiescent state.

Re: LPC11C14 port pull-up resistor value ?

lpcware — Thu, 16 Jun 2016 02:55:34 GMT

Content originally posted in LPCWare by NXP_Europe on Sun Feb 19 03:00:46 MST 2012
[FONT=Arial]Hello DaveNadler,[/FONT]

[FONT=Arial]The pull-up and pull-down 'weaks' are not actual resistors. They are transistors configured as a current source.[/FONT]
[FONT=Arial]They are 'weak' current sources. For simplicity we call them resistors.[/FONT]

[FONT=Arial]What kind of ESD suppression do you have in mind?[/FONT]

[FONT=Arial]Otherwise, I would suggest, if critical, not to use the 'weak' resistor part and to use external resistors.[/FONT]