Tl494 | Circuit Diagram

Programmable frequency generator determined by an external resistor ( RTcap R sub cap T ) and capacitor ( CTcap C sub cap T

Pin 4, the Dead-Time Control, is a safety feature visible in the diagram. It provides a DC offset that limits the maximum duty cycle. This is crucial in push-pull or bridge topologies to prevent "shoot-through"—a condition where both power transistors are on simultaneously, causing a short circuit. The diagram shows this pin feeding directly into the comparator, ensuring that even if the feedback loop demands 100% output, the dead-time control clips the signal to prevent hardware damage.

Never leave unused error amplifier inputs floating. If Error Amplifier 2 is not being used for current limiting, tie its non-inverting input ( , Pin 15) to REF (Pin 14) and its inverting input ( , Pin 16) to GND (Pin 7) . This disables it safely.

Fixed frequency, adjustable via external components. tl494 circuit diagram

The TL494's true power lies in its versatility. Below are several of the most popular and useful TL494 circuit diagrams you can build.

The TL494 circuit works by comparing a linear sawtooth waveform against two control signals to determine the output pulse width. Microcontrollers Lab The Internal Oscillator

The designed primarily for switch-mode power supply (SMPS) applications. Originally engineered by Texas Instruments, this highly versatile 16-pin integrated circuit (IC) contains all the building blocks required to construct a reliable DC-to-DC converter, inverter, or buck/boost regulator. The diagram shows this pin feeding directly into

Compensation input. Used to stabilize the feedback loop. High voltage on this pin reduces the output pulse width.

The two error amplifiers make the TL494 an excellent choice for a sophisticated battery charger that requires both constant current (CC) and constant voltage (CV) regulation.

) as close to the IC pins as possible. Route high-current paths from the switching MOSFETs away from the sensitive reference and feedback traces to avoid electrical noise interference. This disables it safely

Timing capacitor connection for setting the oscillator frequency.

Timing resistor connection for setting the oscillator frequency. Ground connection. 8 Collector terminal of the first output transistor. 9 Emitter terminal of the first output transistor. 10 Emitter terminal of the second output transistor. 11 Collector terminal of the second output transistor. 12 Main power supply input (7V to 40V). 13 OUTPUT CTRL

Controls the minimum dead time between output pulses. Applying 0V allows maximum duty cycle (approx. 45% per output), while 3.3V or higher shuts down the outputs completely.

The TL494 is widely used in various applications, including:

Create a voltage divider from the final output rail down to Pin 1 (1IN+). Connect Pin 2 (1IN-) to a stable reference point, often achieved by splitting the 5V REF (Pin 14) using two equal resistors to get 2.5V. The TL494 will automatically adjust the duty cycle to keep the voltage at Pin 1 equal to Pin 2.