The Zener diode is often used to create a reference voltage. In tutorials and even college texts, there are mentions of creating a Zener diode based regulator. The idea is that the Zener maintains a known voltage drop. The problem is that current matters. This post looks a quick Zener diode overview and shows what happened when I tried to power a microcontroller using a “Zener diode regulator.”

Here are some ideas of what you can do with the humble voltage divider. This elementary circuit has a few inventive uses. To be upfront, one of these uses is NOT as a voltage regulator. If you need a voltage regulated, get a voltage regulator! At some point or another, I’ve built all five of these voltage divider circuits. For me, the voltage level shifter is the most common.

  1. Measure Battery Voltage
  2. Signal Level Shifter
  3. Reference Voltage
  4. R-2R Ladder
  5. One Analog Input with Many Buttons

Digital ICs like microcontrollers, memory, and shift registers need a stable voltage source to make sure they work as expected.  Most circuits are designed with a voltage regulator to accomplish this stability.  In theory voltage regulators will vary their output to stay at a set voltage, regardless of how much current the load is drawing.  As a load draws a little bit more current, the supply voltage will begin to sag.  Conversely when the load is…