I just built a clock generator for testing logic using
The NE555 timer, the output pulse is ok but is 9v, the same as the power supply rail, how can I use 9v power supply but have my square wave output at 5v pk to pk?

 

hi F,
A resistor [390R or 430R] and say a 4.7V zener would be a simple option.
E
EDIT:
A couple of series 2.3V Green diffused LED's in place of the zener would be a nice touch, see that it pulsing at lower rates

 

If you don’t need much current at 5V, you could even get away with a simple resistor voltage divider.

 

What's the impedance of the load you want to drive with the 5V signal?

 

What's the impedance of the load you want to drive with the 5V signal?

I have no idea Crutschow... Will be feeding it into counter chips etc.

 

hi F,
Which type of counters CMOS, TTL etc.??
E

 

I have no idea Crutschow... Will be feeding it into counter chips etc.

Those are relatively high impedance loads, so Eric's circuit should work fine.

 

hi C,
I am a little concerned if the TS is using TTL, a 430R pull down may need a Schottky diodes across the 430R.
E

 

Yes I rather like the idea of a zener, i'll order some and try that.

Thanks folks.