On Sat, 3 Jun 2006, Palaniappan C wrote:

> What is weak pullup ? The strength 'strong' or 'weak' related
> to voltage level or current level ?
>
> I am using PIC18f2525 and datasheet gives only 'weak' pullup current
> and not resistor value,  Why it is ?.
>
> My another doubt is , Weak pullups are done by resistors or active
> components  ? ( Because, In academics, i have read somewhere , it is
> difficult to fabricate passive components on IC than active components).

They are small area PMOS transistors. 'weak' is marketingspeak for the 
more accurate engineering term 'we cannot guarantee much about this, 
take is as it is'. You have to admit that 'weak' sounds better.

Peter
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