UC2845

UNISONIC TECHNOLOGIES CO., LTD UC2844/45 LINEAR INTEGRATED CIRCUIT HIGH PERFORMANCE CURRENT MODE PWM CONTROLLERS „ DESCRIPTION The UTC UC2844/2845 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 UC2844 and UC2845 are the maximum duty cycle ranges and under-voltage lockout thresholds. The UC2844 ideally suited to off-line applications with UVLO thresholds of 16V(ON) and 10V(OFF), and UC2845 has UVLO thresholds of 8.5V(ON) and 7.6V(OFF) for lower voltage applications. „ 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 „ ORDERING INFORMATION Ordering Number Lead Free Halogen Free UC2844L-S08-R UC2844G-S08-R UC2844L-S08-T UC2844G-S08-T UC2845L-S08-R UC2845G-S08-R UC2845L-S08-T UC2845G-S08-T Package SOP-8 SOP-8 SOP-8 SOP-8 Packing Tape Reel Tube Tape Reel Tube www.unisonic.com.tw Copyright © 2012 Unisonic Technologies Co., Ltd 1 of 7 QW-R103-051.B UC2844/45 „ PIN CONFIGURATION LINEAR INTEGRATED CIRCUIT „ PIN DESCRIPTION PIN NO 1 2 3 4 5 6 7 8 PIN NAME Compensation VFB ISENSE RT/CT GND Output VCC VREF FUNCTION Error ...