WT7520 Datasheet | Weltrend Semiconductor

DESCRIPTION The WT7520 is a pulse- width modulation (PWM) control circuit with plete protection circuits for used in the SMPS (Switched Mode Power Supply). It contains various functions, which are Over Voltage Protection, Under Voltage Protection, Power Good Output (PGO), Remote On/Off control and etc. It can minimize external ponents of switching power supply systems in personal puter. Over Voltage Protection (OVP) monitors 3.3V, 5V, 12V and PT input voltage level. Under Voltage Protection (UVP) monitors 3.3V, 5V and 12V input voltage level. Power Good Output monitors the voltage level of power supply. FEATURES - plete PWM Control and Protection Circuitry - Over Voltage Protection for 3.3V / 5V / 12V / PT - Under Voltage Protection for 3.3V / 5V / 12V - 280ms PG Time Delay - Power Good Output is Open Drain Output - PWM Control Output are Open Drain Output - 280 m S Time Delay for UVP - Remote ON/OFF function De- bounce Time - Soft-Start function built-in - 16- Pin Dual In- line Package PIN CONFIGURATION V33 V5 V12 PT GND RT C1 C2 1 16 2 15 3 14 4 13 5 12 6 11 7 10 89 VADJ OPNEGIN OPOUT VCC DET PG SS REM Ordering Number WT7520 Package Type DIP 16 Weltrend Semiconductor, Inc. Page 2 Data Sheet Rev. 0.90 PIN DESCRIPTION Pin No. 1 V33 2 V5 3 V12 4 PT 5 GND 6 RT 7 C1 8 C2 9 REM Pin Name 10 SS 11 PG 12 DET 13 VCC 14 OPOUT 15 OPNEGIN 16 VADJ TYPE I I I I P O O O I I P O I I FUNCTION OVP/UVP input FOR 3.3V. OVP/UVP input for 5V. OVP/UVP input for 12V. Extra OVP protection input. Ground. Oscillation frequency set by external resistor. PWM open drain output 1. PWM open drain output 2. Remote on/off input. REM=”low” that means the main SMPS is turned-on. REM=”high”, the main SMPS is turned-off. Soft start function set by external capacitor. Power good signal. PG= ”high” means “power good”. PG= ”low” means “power fail”. Extra protection input. Supply voltage. OP pensation output. OP pensation negative input. OP pensation positive input , feedback...