I am not sure exactly what you mean but lets start easy . If you want to reset a batch of logic (cmos / TTL) then I use a simple resistor and capacitor (1 meg .1uf) in series withe the centre point to the reset pins. If you have to start with a low then have the capacitor to ground and of course vice versa.
i really appreciate your responses. i'm trying to reset an HC11 MCU. i remember reading somewhere that a simple resistor/capacitor is not always the right way to go due to poor power supply during power on reset. (i think it's call brown out effect). so i guess i'm looking to design a power good circuit that assures that the power is good and then activates the resistor/capacitor to cause a reset signal. thanks!
i'll check out the ic that sebi suggested too. thanks!
The group of ICs for this are called Supervisor ICs. There is a very large group of them. MAXIM, TI, Linear Technologiy make them.
Some of them even have hardware watchdog circuits so that your processor can never crash. (You can't shutdown those)
For example the following has control options for battery Backed-up RAM gating signals. https://www.linear.com/prod/datasheet.html?datasheet=321
If you search manufacturer web sites with "supervisor" keyword you'll find what you need.
There's a good selection of easy reset chip out there
...but please consider MAX809 or MAX810 from.... PHILIPS Semi.!!! YES - sounds like a MAXIM, but these are Dutch chips
Costs ~0.25euro, so this is peanut comparing sleepless nights of wondering does it hang up, or not (of course after delivery to customer).
And last but not least: it needs NO EXTERNAL components. Housed in small, nice SOT-23.
Watch the attachement for full specs (Vtreshold, output polarization etc.)