Electronics & Electrical Engineering Forum:
Getting Noise on a mV range Square Wave Generator
I’m in the process of designing a Square Wave Generator that is capable of operating at millivolt levels.
The circuit uses a MIC1557 timer/oscillator to generate a 5V square wave.
Three op-amps are being used to divide the voltage down by increments of 10. A fourth op-amp is attached to a 10-turn pot to enable adjustment of the amplitude of the wave from 0 to 50mV.
I’ve attached a photo of the oscilloscope showing the Square Wave Generator set to a 1mV output.
The waveform looks ok overall but is relatively noisy and that is where I am having problems. I’m not used to working at these voltage levels, so any advice or help would be most welcome.