Mike Deblis said:
Title says it all, really... I want to have a couple of interconnected
monostables but am not at all sure how to do it... I may be missing
the obvious...
Any ideas gratefully received...
Hello Mike,
there are models for a 74HC(t)123 and TLC555 in the "Files" section of
the LTSPICE-Yahoo group.
www.groups.yahoo.com/ltspice
The basic idea:
You could use a flipflop set by the edge of a trigger impuls.
After the FF is triggered, the OD switch is off and thus the
capacitor is charged via resistor R. Finally the FF will be
reset after the voltage of the capacitor has reached a certain
level, e.g. 2/3 of Vcc like in the lm555.
Some additional circuit is needed if you want features like
retrigger capabilty.
+
|
|R|
|
+-----------------------------------
Trig. v | |
-->|Flipflop|-+-|OD|--+-----|Schmitt-Inv.|--
| |C|
out |
---
OD = open drain buffer or mosfet
Schmitt-Inv. = Schmitt trigger inverter
Best Regards,
Helmut
