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 8.4 V and turn off at 7.6 V.

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

• 2.0% 5.0 Volt Reference

• High Current Totem Pole Output