I want to convert a differential signal to single-ended for use on a microcontroller’s digital input, but do not know which differential amplifier to use.
The signal originates from a digital quadrature encoder, which outputs differential digital signals of 0V or 5V. The complement pairs A+/A- and B+/B- always output opposite values (0V/5V for LOW, or 5V/0V for HIGH). If possible, the amplifier should be able tolerate signal frequencies up to the megahertz range, as this encoder generates 4000 pulses per revolution, and may run up to 10krpm.
I have tried reading the signals as single-ended by ignoring A- and B-, but this fails due to noise from the power supply.
The power supply generates identical ripples in all 4 signals (approximately -1V to +1V). Unfortunately, this input ripple cannot be avoided as it is powered by a motor controller’s internal logic power.
I hope to effectively filter this ripple by converting the A+/A- and B+/B- differential signal pairs to single-ended. The microcontroller’s 5V power supply is available, which is free from noise to my knowledge.
All help is greatly appreciated.
