mode at a 50% duty cycle? All the circuits I've seen are always for
I just googled 555 50% PWM and got :
http://www.dprg.org/tutorials/2005-11a/index.html
Look at what is done with the diodes D1 and D2
Jim
The CMOS version of the 555 (e.g. 7555) is far superior to the Bipolar
version (e.g. NE555) for a variety of reasons. Reason 1 is reduced power
consumption. Reason 2 is the absence of the quirky short circuit spike (400
ma) during an output transition. Reason 3 is that output levels of the CMOS
version approach the supply rails (ground or common and VCC) as they should.
Also I believe the voltage divider resistors in the bipolar version are 1K
while they are 100K or more in the CMOS version. This is very useful if
you're modulating the pin 5 voltage level.
Hooking the output of the 555 (pin 3) to the RC network will give you a 50%
duty cycle as John mentioned and this always works best with the CMOS
version.
Dorian