Square Wave Oscillator

Description:

A very basic square wave generator using a CMOS 4011 NAND gate.

Notes

Using two gates from a CMOS 4011 NAND chip, a simple squarewave oscillator can be made. Pinouts for the CMOS 4011 can be found in the practical section click here. All unused inputs should be tied to ground. Alternatively a CMOS 4001 chip can also be used, or a TTL equivalent. In this circuit the mark space ratio can also be independantly controlled by varying the value of the resistors. The rise and fall times of the output pulses depend on the operating voltage of the IC and type of IC, but will be typically in the order on tens of nanoseconds.