Even with a good model, simulations fail. Here’s the troubleshooting checklist:
This is the most common hurdle. LTspice does not ship with a native TL494 model. You have three options:
First, create this file as TL494.sub in your LTspice working directory. tl494 ltspice
* TL494 Subcircuit for LTspice * Pin order: 1IN+ 1IN- 2IN+ 2IN- FB COMP CT RT GND C1 C2 VCC OUT1 OUT2 * Simplified functional model: oscillator, PWM comparator, error amps, outputs.SUBCKT TL494 1 2 3 4 5 6 7 8 9 10 11 12 13 14
.ENDS TL494
Instead of building from scratch, leverage existing work: Even with a good model, simulations fail
Download package checklist:
Always verify the model’s dead-time behavior by plotting the output against the ramp. Instead of building from scratch, leverage existing work: