TL494CN

The TL494 device incorporates all the functions required in the construction of a pulse-widthmodulation (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 ΔV. The dead-time control comparator has a fixed offset that provides approximately 5% dead time. The 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 in synchronous multiple-rail power supplies. The uncommitted output transistors provide either common-emitter or emitter-follower output capability. The TL494 device provides for push-pull or singleended output operation, which can be selected through the output-control function. The architecture of this device prohibits the possibility 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 is characterized for operation from -40°C to 85°C.

Applications

• Desktop PCs
• Microwave Ovens Power Supplies: AC/DC, Isolated, With PFC, >90 W
• Server PSUs
• Solar Micro-Inverters
• Washing Machines: Low-End and High-End
• E-Bikes Power Supplies: AC/DC, Isolated, No PFC, <90 W
• Power: Telecom/Server AC/DC Supplies: Dual Controller: Analog
• Smoke Detectors
• Solar Power Inverters

Key features

• 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