General Description

The AZ494A/C is a voltage mode pulse width modulation switching regulator control circuit designed primarily for power supply control.

The AZ494A/C consists of a reference voltage circuit, two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, and an output control circuit. The precision of voltage reference (VREF) is improved up to ±1 through trimming and this provides a better output voltage regulation. The AZ494A/C provides for push pull or single-ended output operation, which can be selected through the output control.

The difference between AZ494A and AZ494C is that they have 4.95V and 5V reference voltage respectively.

The AZ494A/C is available in standard packages of DIP-16 and SOIC-16.

特性 Features

· Stable 4.95V/5V Reference Voltage Trimmed to ±1.0 Accuracy

· Uncommitted Output TR for 200mA Sink or Source Current

· Single-End or Push-Pull Operation Selected by Output Control

· Internal Circuitry Prohibits Double Pulse at Either Output

· Complete PWM Control Circuit with Variable Duty Cycle

· On-Chip Oscillator With Master or Slave Operation

Applications

· SMPS

· Back Light Inverter

· Charger