KA3504 Datasheet | Fairchild Semiconductor

.fairchildsemi. PC SMPS Supervisory IC Features - - - - - - - - - - - - PC Power Supply Output Monitor Circuitry Few External ponents Over Voltage Protection for 3.3V/5V/12V Output Over Current Protection for 3.3V/5V/12V Output With Delay Time Fault Protection Output With Open Collector Output Power Supply on/off Delay Time Control (PSON) Power Good Signal Generator With Hysteresis Open Collector PG Output 300ms Power Good Delay Current Sense Setting Function With RI Latch Function Controlled by PSON and Protection Input 16-Pin Dual In-line Package Description The KA3504 is plete output supervisory circuitry intended for use in the secondary side of the switched mode power supply. It provides all the functions necessary to monitor and control the output of the power supply system. Power good signal generator, Remote on and off control, some precision protection Features against over-voltage and over-current are implemented. It directly senses all the output rails for OVP without any external dividers. As for output control, power good output (PGO) and Fault Protection output (FPO) are also included. Utilizing a minimum number of external ponents, the KA3504 offers a simple and cost effective solution, greatly reducing PCB board space for power supply system. OCP (Over Current Protection) FPO (Fault Protection Output) Fault Protection Output indicates the fault condition as protection signal. When fault state occurs, the main power is to be turned-off and the PGO signal goes LOW. NORMAL = "LOW", FAULT = "HIGH" It has precision OCP functions for +3.3V, +5V, +12V outputs. The block is made up of three parators with current source setting function. Two inputs of each OCP parator are connected to both sides of output inductor that is located in the secondary output of SMPS. OVP (Over Voltage Protection) PGO (Power Good Output) Power Good Signal Generator is to monitor the voltage level of power supply for safe operation of a...