Tl494 Ltspice Info

| Pin | Name | Description | |-----|-----------|---------------------------| | 1 | IN1+ | Error Amp 1 non‑inverting | | 2 | IN1- | Error Amp 1 inverting | | 3 | FEEDBACK | Compensation / PWM input | | 4 | DTC | Dead‑time control | | 5 | CT | Timing capacitor | | 6 | RT | Timing resistor | | 7 | GND | Ground | | 8 | C1 | Output collector 1 | | 9 | E1 | Output emitter 1 | | 10 | E2 | Output emitter 2 | | 11 | C2 | Output collector 2 | | 12 | VCC | Supply (7–40 V) | | 13 | OUT_CTRL | Output mode control | | 14 | REF | 5 V reference output | | 15 | IN2- | Error Amp 2 inverting | | 16 | IN2+ | Error Amp 2 non‑inverting |

Connect Pin 13 directly to GND . Both output transistors switch simultaneously, permitting a maximum duty cycle near

Related search suggestions provided.

* VREF Generator (Pin 14) B1 14 7 V=5

: This pin dictates the output mode. If you tie it to ground, you enable push-pull mode where the outputs alternate. If you tie it to the 5V reference on pin 14, you enable single-ended mode, allowing both outputs to switch simultaneously but with a maximum duty cycle of about 96%. Using the wrong mode for your intended application will lead to incorrect waveforms.

To simulate the classic within Analog Devices LTspice , you must use a third-party SPICE subcircuit model ( .sub or .lib ) paired with a custom symbol file ( .asy ) . Because Texas Instruments does not provide an official SPICE model for this legacy chip, designers rely on open-source macro-models to replicate its internal oscillators, error amplifiers, and steering logic.

The TL494 remains a popular choice for educational projects and legacy designs due to its low cost, availability, and versatility in topologies like buck, boost, push-pull, and flyback converters. Simulating it in LTspice allows you to validate your control loop, observe switching behavior, and optimize component values without the risk of burning out hardware. tl494 ltspice

You can download it from:

The TL494 integrates all the functions needed for pulse-width modulation (PWM) control on a single chip:

LTspice does include a TL494 model by default. You have three options: If you tie it to ground, you enable

: A widely cited model can be found on this forum thread . 2. Import the Model into LTspice

* Dead Time & PWM Logic (Pin 4) * Dead time voltage effectively offsets the sawtooth floor or clamps the comparator. * If V(4) > Sawtooth, Output is OFF. * Effective PWM comparator: Duty Cycle = (V_saw - V_dead) / V_saw_amp.

This article is a comprehensive, end-to-end guide. It will navigate you through the challenges of finding a functional model, integrating it into LTspice, understanding the critical circuit parameters that dictate success, and systematically troubleshooting the most common errors. By the end, you will have a robust methodology for simulating your TL494-based power supply designs with confidence. To simulate the classic within Analog Devices LTspice