* PWM Comparator Logic * Sawtooth internal node (assume node 100) B2 100 0 V=IDTMOD(I=10m, MODE=1) ; Simplified ramp generator for logic B3 101 0 V=IF(V(100) > (V(3)+V(4)), 0, 1)

| File | Purpose | |------|---------| | TL494.sub | Subcircuit definition (Spice netlist) | | TL494.asy | LTspice schematic symbol | | TL494_test.asc | Example test circuit |

Some models may not properly handle extreme dead-time settings; ensure DTC is properly biased.

When it comes to designing switching power supplies and PWM controllers, the TL494 integrated circuit has been an industry workhorse for decades. This versatile PWM control IC can be found in buck, boost, flyback, forward, push-pull, half-bridge, and full-bridge converter designs — essentially any power topology imaginable. However, getting the TL494 to work correctly in LTspice simulations has become a common challenge that frustrates even experienced engineers.

This is classic in switching converters.

The used heavily in switch-mode power supplies (SMPS), DC-DC converters, and inverter designs. Simulating this versatile controller in Analog Devices LTspice allows you to test feedback loops, adjust dead-time control, and verify circuit stability before building physical hardware.

The TL494 shines in push-pull because of its alternating output stages.