Creating PWL Files For LTSpice for PWM Signals
Here is a very simple tool that can be used to simulate producing sine waves from PWM pulses and an appropriate filter in LTSpice. It can be downloaded and built or run online…
The source code is in C++ and available on github. The same code can be run here in a webpage (read more about how that can be achieved - and should run here:
For example, if we were to use this to try and simulate PWM outut of a teensy 4.1 with the following parameters:
- Resolution 8 Bit
- Frequency 585937.5Hz
- Rise/Fall 10pS (arbitrary)
- Update Every 2 cycles
- Low/High 0 / 3.3v
It would produce a file that could be read into LTSpice, which, in the following basic circuit
when run would produce the following waveforms
When implemented in a real ciruit:
the waveform on a scope is thus:
