The TL494 device incorporates all the functions required in the construction of apulse-width-modulation (PWM) control circuit on a single chip. Designed primarily for power-supplycontrol, this device offers the flexibility to tailor the power-supply control circuitry to aspecific application.
The TL494 device contains two error amplifiers, an on-chip adjustableoscillator, 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 toVCC – 2 V. The dead-time control comparator has a fixed offset that providesapproximately 5% dead time. The on-chip oscillator can be bypassed by terminating RT to thereference output and providing a sawtooth input to CT, or it can drive the common circuits insynchronous multiple-rail power supplies.
The uncommitted output transistors provide either common-emitter or emitter-followeroutput capability. The TL494 device provides for push-pull or single-ended output operation, whichcan be selected through the output-control function. The architecture of this device prohibits thepossibility of either output being pulsed twice during push-pull operation.
The TL494C device is characterized for operation from 0°C to 70°C. The TL494I device ischaracterized for operation from –40°C to 85°C.