Description

The CS52843 provides all the necessary features to implement off line fixed frequency current-mode control with a minimum number of external components.

The CS52843 incorporates a new precision temperature-controlled oscillator to minimize variations in frequency. An undervoltage lockout ensures that VREF is stabilized before the output stage is enabled. In the CS52843 turn on is at 8.4V and turn off at 7.6V.

Other features include low start-up current, pulse-by-pulse current limiting, and a high-current totem pole output for driving capacitive loads, such as gate of a power MOSFET. The output is low in the off state, consistent with N-channel devices.

Features

■ Optimized for Off-line Control

■ Internally Temperature Compensated Oscillator

■ VREF Stabilized before Output Stage is Enabled

■ Very Low Start-up Current 300 µA (typ)

■ Pulse-by-pulse Current Limiting

■ Improved Undervoltage Lockout

■ Double Pulse Suppression

■ 2% 5 Volt Reference

■ High Current Totem Pole Output