Need help designing 40khz Square wave generator circuit

[HBKss]

Hi,
I need help designing a 40khz square wave generator. I have seen circuits online, they use 741 amplifier ic but i could nt get the desired frequency, The max frequency i got was 210 khz. Also the wave was not symetrical(ie +ve and -ve cycles were not of same time). Kindly help me Thanx

 

[ronsimpson]

What output voltage? 5V & 0V or +1 & -1V????
40khz +/-5% or 1% or 0.00001%?

 

[jpanhalt]

There are hundreds, if not thousands, of 555 and Schmitt inverter designs that will produce nice 40 KHz square waves.

Why did you choose something with a 741? Are we talking about the same thing?

John

 

[alec_t]

The max frequency i got was 210 khz

I'd be very surprised if you could get anything like a square wave out of a 741 at that frequency!