TL494 PWM Control Circuit

The TL494 device incorporates all the functions required in the construction of a pulse-width-modulation (PWM) control circuit on a single chip. Designed primarily for power-supply control, this device offers the flexibility to tailor the power-supply control circuitry to a specific application. The TL494 device contains two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, a 5-V, 5%-precision regulator, and output-control circuits. The error amplifiers exhibit a common-mode voltage range from –0.3 V to VCC – 2 V. The dead-time control comparator has a fixed offset that provides approximately 5% dead time. The TL494 on-chip oscillator can be bypassed by terminating RT to the reference output and providing a sawtooth input to CT, or it can drive the common circuits insynchronous multiple-rail power supplies.

Features of  TL494 Pulse Width Modulation (PWM)

• Complete PWM Power-Control Circuitry

• Uncommitted Outputs for 200-mA Sink or Source Current

• Output Control Selects Single-Ended or Push-Pull Operation

• Internal Circuitry Prohibits Double Pulse at Either Output

• Variable Dead Time Provides Control Over total range

• Internal Regulator Provides a Stable 5-V Reference Supply With 5% Tolerance

• Circuit Architecture Allows Easy Synchronization

Applications of  TL494 Pulse Width Modulation (PWM)

• Desktop PCs

• Microwave Ovens

• Power Supplies: AC/DC, Isolated with PFC, >90W

• Smoke Detectors

• Solar Power Inverters

• E-Bike