器件名称: DI-57
功能描述: 60 W DC-DC Converter
文件大小: 57.67KB 共2页
简 介:Design Idea DI-57 DPA-Switch
60 W DC-DC Converter
Application Telecom Device DPA426R Power Output 60 W Input Voltage 36-75 VDC Output Voltage 12 V Topology Flyback
Design Highlights
Low cost 400 kHz flyback design Simple Zener referenced 12 V output Efficiency – 82% at 36 VDC and full load Low component count Accurate line OV and UV protection Thermal, short circuit and output overload protection No current sense components
minimize fault and overload power. Drain voltage clamping is provided by diode D4 and Zener diode VR1 with optional components C4 and R2 to provide high frequency snubbing. The output is rectified by diode D2 with optional high frequency damping from components C9, R15 and R16. The output capacitors are alternated to share the ripple current evenly between the Oscon capacitors (C10-14) and the ceramic capacitors (C15-C18). A final decoupling ceramic capacitor C19 is placed at the output pins of the power supply. Output regulation is taken from the +12 V output. Zener diode VR2 is DC-biased by resistor R7 with the opto-diode of U2 providing feedback and resistor R6 programming the gain. Optional capacitor C8 implements a soft-finish network to slow the rise of the output voltage at start-up.
R15, R16 33 1/4 W
Operation
DPA-Switch greatly simplifies the design compared to a discrete implementation. Resistor R1 programs the under/over voltages and linearly reduces the maximum duty cycle with input voltage to prevent core saturation during load t……