I use the MAX1232 as watchdog and reset circuit but without any problems.

So it seems, using MAXIM was a good choice.


Unfortunately I read the data sheet not carefully enough and assumed, it can be disabled with the watchdog input floating like the MAX690.

Thus I switched now to the MAX813L, which give me also a high active reset but can be disabled by a jumper during developing software.

I like such always watchful devices, which can only be disabled by hardware. And I trust never an internal watchdog of a micro.
Since microcontroller developers are only experts in running software and supervisor developers are the only experts on power on behaviour and noise influence. And until today I have never seen, that both experts join together.


On earlier projects I had trouble by replacing the MAX690 with the ADM690. On reading an older data sheet, both seems identical, but a newer data sheet tells me, they are different. I go back to the MAX690 and it works again.

After this I know, the same number from a different manufacturer can cause a different working !!!



Peter