Tl494 Ltspice

Copy and paste this into the LTspice schematic window:

To accurately simulate the device, one must understand its four distinct internal blocks. tl494 ltspice

The TL494 is primarily voltage-mode. However, you can implement current-mode by feeding the current sense signal into the second error amplifier (pins 15/16) and OR-ing it (via diode) to the compensation pin. Simulating this requires careful tuning of the current ramp slope compensation to avoid subharmonic oscillations. Copy and paste this into the LTspice schematic

Since there is no official Texas Instruments model for LTspice, the most cited "working" versions are found in these community repositories: tl494 ltspice

A common way to verify the TL494 model is by simulating a standard buck converter. LTSpice - Importing a New Component Model for Simulation