The good news is that a comparator-based buffer will typically be a lower power solution than an op amp. The bad news is the tendency of the comparator-based buffer is overshoot. These students show a ...

The ATtiny85’s Analog Comparator function is perfectly suited for such a tester. One input of the comparator is biased such that there is a 51 ohm resistor between the input and ground.

Precision instruments often contain specialized components that are essential to their function, but nearly impossible to replace if they fail. [Andre] had just such a problem with an optical compa… ...