Convert Signals To Proper Logic Levels

摘要

When designing a test station incorporating a microcontroller, you often face voltages in the test that exceed the maximum input level permitted for the microcontroller. For example, if a microcontroller uses a 5V power supply, then the maximum input signal should also be 5 V. When a test voltage exceeds 5V, you might think to reduce the voltage with a voltage divider. A voltage divider can influence the DUT (device under test), however. So, a signal conditioner needs high input impedance. Also, the signal conditioner's output signals should match the logic levels of the microcontroller despite some fluctuation of the measured signal. It allows you to use the regular microcontroller-input pins instead of ADC ones.