UC3844/UC3845中文资料HIGH PERFORMANCE CURRENT MODE PWM CONTROLLERS数据手册UTC规格书

描述 Description

The UTC UC3844/3845 are high performance fixed frequency current mode controllers that specifically designed for Off-Line and DC to DC converter applications with minimal external parts count. The differences between UC3844 and UC3845 are the maximum duty cycle ranges and under-voltage lockout thresholds. The UC3844 ideally suited to off-line applications with UVLO thresholds of 16V(ON) and 10V(OFF), and UC3845 has UVLO thresholds of 8.5V(ON) and 7.6V(OFF) for lower voltage applications.

特性 Features

Operation output switching frequency up to 500 kHz  
Output deadtime adjustable from 50% to 70%
Automatic feed forward compensation
Latching PWM for cycle-by-cycle current limiting
High current totem pole output
Internally trimmed reference with under voltage lockout
UVLO with hysteresis
Low startup and operating current