Re: Upper limit of timing resistor value in a tropical setting

On a sunny day (Fri, 20 Sep 2024 14:18:26 +0530) it happened Pimpom
<Pimpom@invalid.invalid> wrote in <vFaHO.92333$lZG8.68980@fx09.ams1>:

Take a typical domestic environment in a tropical region, rather humid
at times. Assembled board is not conformal coated and some dust is
expected to seep into the box over the years and settle on the PCB. The
unit is low voltage and low power with just a few watts dissipated when
on, and left unpowered for days on end.
>
An R-C combination is used to set timing of around 1 sec. which is not
critical (long-term variation of up to 10% is tolerable). If it gets
very bad, the board can be cleaned but this should not be required as
regular maintenance.
>
Under these circumstances, what's the highest timing resistor value
you'd feel comfortable with?

100 k would be a high limit
10k 22k better
But s Microchip PIC with internal clock is slightly temperature sensitive
but can create any timer, uses almost no power, and can do many more things.
Requires some programming though.
No timing caps and resistors needed...