Tl494: Ltspice

This guide shows how to model, simulate, and use the TL494 PWM controller in LTSpice for common switched‑mode power supply tasks. It includes a compact behavioral subcircuit, examples (buck converter, push‑pull), control‑loop tips, and troubleshooting notes so you can get realistic, useful results fast.

The LTspice user group on groups.io maintains a collection of models and libraries. The TL494 model can be found in the z_yahoo/Lib/TL494/ directory. Additionally, the LTwiki provides a comprehensive Standard.zip library containing many useful models.

Place the matching graphical component file TL494.asy inside the symbol directory: \Documents\LTspice\lib\sym\ tl494 ltspice

Dual transistors capable of collector-emitter sourcing or sinking up to 200mA, adding immense drive flexibility. Sourcing and Installing the TL494 LTspice Model

Limit the maximum time-step in your simulation configuration directive. A command like .tran 0 2m 0 10n forces a tight 10-nanosecond window, preventing the solver from jumping past critical switching edges. This guide shows how to model, simulate, and

7 = CT 8 = RT 9 = GND 10 = C1 11 = C2 12 = VCC

If you don’t want to copy files to LTspice’s program directories: The TL494 model can be found in the

COMP pin pullup to internal reference (~3.5V) R_COMP 6 100 10K

If you tell me what specific converter type you are building (Buck, Boost, Push-Pull), I can provide a detailed schematic snippet or help you optimize your compensation loop . Share public link

Move this file into C:\Users\[YourUsername]\Documents\LTspiceXVII\lib\sym\PowerProducts\ (or the corresponding directory for LTspice 17/24).

For (e.g., Buck or Boost), the output switching frequency equals the oscillator frequency: