First, there must be a signal source with the frequency of 10kHz, and then it will be converted into a square wave with the same frequency by a shaping circuit.

The simplest and most accurate method of 10kHz signal source is to use active crystal oscillator, and CMOS Schmidt inverter is the simplest for shaping circuit. Generally, a square wave can be obtained from any waveform signal source (such as sine wave, triangular wave, sawtooth wave, trapezoidal wave, etc.). After one-level inversion, a high-quality standard square wave can be obtained after at most two-level inversion.