Tl494 Ltspice [portable] Jun 2026

* TL494 behavioral subckt (switch-level) * Pins: VCC GND FB COMP RT CT DTC SS OUTC OUTE ILIM .SUBCKT TL494 VCC GND FB COMP RT CT DTC SS OUTC OUTE ILIM * Internal nodes .node 1 2 3 4 5 * Reference 5V (approx) BREF REF GND V=V(VCC)*0.08 ; simple reference scaled from VCC (adjust as needed) * Oscillator: ramp from C RRT RT REF 100k CCT CT REF 10n * Use behavioral current to form saw; simplistic: I = k/RT BIOSC SAW REF I=V(VCC)/(100k) ; replace with better oscillator if needed * Error amplifiers (inverting inputs: FB, ILIM; non-inv to reference) * EA1: drives COMP node EEA1 COMP GND VALUE = clamp( (V(REF)-V(FB))*10, -5, 5 ) * PWM comparator with deadtime (DTC pin sets min-off) BPD CMP_OUT GND V= if( V(COMP) > V(SAW)*(1 - V(DTC)/5), 1, 0 ) * Outputs: open-collector to drive gate driver resistor network * OUTC and OUTE are complementary PWM outputs (simple) EOUTC OUTC GND VALUE= V(CMP_OUT) ? 0.1 : 0 ; low impedance sink when active EOUTE OUTE GND VALUE= !V(CMP_OUT) ? 0.1 : 0 * Soft-start: clamp COMP by SS voltage BSS COMP LIMIT GND V= min(V(COMP), V(SS)) * Current limit sense: if ILIM > threshold reduce duty BLICM COMP GND V= if( V(ILIM) > 0.5, V(COMP)*0.5, V(COMP)) .ENDS

To use the in LTspice, you must use a third-party subcircuit because there is no native, official model provided by Linear Technology (Analog Devices) [2]. 1. The TL494 Subcircuit Code tl494 ltspice

The .step command sweeps the load resistance from 5Ω (1A) to 1Ω (5A) and 10Ω (0.5A). Watch how the duty cycle adjusts to maintain 5V output. * TL494 behavioral subckt (switch-level) * Pins: VCC

While Texas Instruments (TI) provides models for PSpice, getting them to play nice with LTspice requires a few extra steps. Here is how to get your simulation running. 1. Sourcing the Model While Texas Instruments (TI) provides models for PSpice,

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