描述 Description

GENERAL DESCRIPTION
The CM3842/43 are fixed frequency current-mode PWM controllers specially designed for OFF-Line switching
power supply and DC-to-DC converters with a minimum number of external components. These devices feature
a trimmed oscillator for precise duty cycle control, a temperature compensated reference, high gain error amplifier, current sensing comparator, and high current totem pole output which is suitable for driving MOSFETs.FEATURES
Low Start-Up current ( typ. 200μA)
Optimized for Off-Line and DC-to-DC Converters
Maximum Duty Cycle
U.V.L.O. with Hysteresis
Operating Frequency Up to 500KHz
Internal Trimmed Bandgap Reference
High Current Totem Pole Output?
Error Amplifier With Low Output Resistance
Available in 8-Pin Plastic DIP and Surface Mount 8-Pin S.O.I.C.APPLICATIONS
Off-line flyback or forward converters.
DC-to-DC buck or boost converter.
Monitor Power Supply

特性 Features

Low Start-Up current ( typ. 200μA)
Optimized for Off-Line and DC-to-DC Converters
Maximum Duty Cycle
U.V.L.O. with Hysteresis
Operating Frequency Up to 500KHz
Internal Trimmed Bandgap Reference
High Current Totem Pole Output?
Error Amplifier With Low Output Resistance
Available in 8-Pin Plastic DIP and Surface Mount 8-Pin S.O.I.C.