Making a point the hard way.

The Electrical Engineering Stack Exchange strikes again.

Due to a disagreement on the EE Stack Exchange about what the current/voltage curve for a particular NPN transistor circuit would look like, I have built a current/voltage (IV) curve tracer for bipolar junction transistors. It has limited scope and capability, but it was good enough for what I needed.

I bashed it together in just a couple of hours, but it looks like describing and justifying all the things I did by “eyeball” is going to be more complicated. I’m also going to make a nice GUI for it, which will take a bit more time.

  1. Building an IV plotter from an Arduino Nano - Why am I doing this? - When I’m right, I’m right.
  2. Building an IV plotter from an Arduino Nano - Generating the bias voltage with stone knives and bearskins - Use what you’ve got.
  3. Building an IV plotter from an Arduino Nano - Measuring current with an Arduino - Ohm’s law doesn’t require a current shunt.
  4. Building an IV plotter from an Arduino Nano - Adding it all up - Just do the easy stuff in the Arduino.
  5. Building an IV plotter from an Arduino Nano - A simple Python program to get started - Just doing some math and writing a bunch of numbers to a file.
  6. Building an IV plotter from an Arduino Nano - Refocusing on the task - Forget the ‘gators, I was supposed to be doing something else.
  7. Building an IV plotter from an Arduino Nano - Back on track and making progress - A functional tracer with revised hardware and software.
  8. Building an IV plotter from an Arduino Nano - Fixing some bugs and changing names - Oversampling by any other name is just as slow.
  9. Building an IV plotter from an Arduino Nano - Now that I’ve got it, how do I use it? - Designing a common emitter amplifier with Rodriguez.
  10. Building an IV plotter from an Arduino Nano - Designing a common emitter amplifier with Rodriguez - part 2 - Lets take a “do over” on that biasing.
  11. Building an IV plotter from an Arduino Nano - Designing a common emitter amplifier with Rodriguez - part 3 - Revising Rodriguez’s base current measurements.
  12. Building an IV plotter from an Arduino Nano - Designing a common emitter amplifier with Rodriguez - part 4 - Three time’s a charm.
  13. Building an IV plotter from an Arduino Nano - Taking a look at a tunnel diode - Surprise time.