KA3501

www.fairchildsemi.com KA3501 PC SMPS Supervisory IC Features Description • • • • • • • The KA3501 is complete housekeeping circuits for use in the secondary side of SMPS(Switched Mode Power Supply). This IC(Integrated Circuit) contains a precision voltage reference, protection circuits and a power good signal generator. It also has a high current drive output for use in conjunction with an external "crowbar" SCR. The reference voltage is trimmed to ±2% for correct output voltages(+5V/ +12V) and power good signal generator is to monitor the voltage level of power good supply for safe operation in a microprocessor circuit. Using the KA3501 requires few external components to accomplish a complete housekeeping circuit for SMPS(Switched Mode Power Supply). The KA3501 is available in an 14-pin DIP. Complete House Keeping Circuit Few External Components Positive Voltage Protection Negative Voltage Protection High Current Drive Output for SCR Precision Voltage Reference for 5V/12V Outputs Power Good Signal Generator with Hysteresis 14-DIP 1 Internal Block Diagram Vcc Vcc1(+5V) Vin1 POSITIVE +5V VOLTAGE START UP PROTECTION Ichg DETECTING COMP Vin2 PG NEGATIVE VOLTAGE INTERNAL PROTECTION BIAS GATE Vcc Ve DETECTING Feedback COMP +2.5V REFERENCE VOLTAGE Vref Vcc2(+12V) Vcont GND Td Timing Rev. 5.0 ©2000 Fairchild Semiconductor International KA3501 Pin Assignments #14 #1 Feedback Vcont GND Vref Vcc2 Vcc1 Vin2 K A 3 5 0 1 Gate 2 1 Vcont 2 Vref Tim ing Vin1 #7 Pin Name PG Td Vcc Pin Number Ve #8 Pin Function Descrition Reference Voltage Control Precision Reference Voltage 3 Vcc2 +12V Output Voltage 4 Vcc1 +5V Output Voltage 5 Vin2 UVP Input (Negative) 6 Gate Gate Drive Input for SCR 7 Vcc Supply Voltage 8 Vin1 PG Input 9 Td 10 Timing PG Delay 11 PG PG Output 12 Ve PG Ground (Open Emitter) 13 GND 14 Feedback Reference Voltage Delay for PG Ground Feedback for Precision Reference KA3501 Absolute Maximum Rating ( Ta = 25°°C) Parameter Symbol Value Unit Supply Minimum Voltage Vcc(min) 5 V Supply Maximum Voltage Vcc(max) 32 V UV Input Voltage Vuv 24 V Minimum Gate Drive Current IDR -25 V Operating Cathode Current IK 1 to 30 A Power Dissipation Pd 1 W Topr 0 to 70 °C Operating Temperature Range Electrical Characteristic (Refer to the test circuit , Vcc=20V, Ta=25°C, unless otherwise stated) Parameter Temperature Stability for VREF Symbol Conditions Min. Typ. Max. Unit ∆VREF - - 17 - mV VPOSI - 5.7 6.0 6.4 V PROTECTION SECTION Positive Protection Voltage Negative Protection Voltage VNEGA Vcc1 = 5V -1.5 -2.5 -3.5 V Negative Input Resistor RNEGA Pin 4 to Pin 5 8.5 10 11.5 KΩ VGATE = 0.7 V -25 -50 - V IK = 10mA 2.44 2.50 2.56 V Gate Drive Current IDR REFERENCE SECTION Reference Input Voltage Current Stability Absolute Precision of Internal Three Resistors Relative Deviation of Three Resistors Temperature Stability (Note 1) Gain Bandwidth (Note 1) VREF ∆VREF - 5 20 mV Rint - - - ±15 % Rrate - - ±0.5 ±3 % Ta = 0 to 70 °C - 13 17 mV GV = 1 - 1 - MHz ∆VREF GBW IK=1mA to 10mA POWER GOOD SECTION Detecting Input Voltage VIN1 - 1.23 1.28 1.33 V Detecting PG Voltage VDET - 4.1 4.3 4.5 V Hysteresis Voltage 1 HY1 - 10 20 40 mV Hysteresis Voltage 2 HY2 - 200 250 - mV Charging Current for PG Delay ICHG - -8 -14 -20 uA PG Output Resistor RPG - 7.7 9.0 10.3 KΩ PG Output Saturation Voltage VSAT ISINK = 6mA - 0.2 0.4 V IO(LKG) - - 0.01 1 uA Icc VCC = 20V , VCC1 = 5V - 3 5 mA PG Output Leakage Current TOTAL STANDBY CURRENT Supply Current Notes: 1.These parameters, although guaranteed, are not 100% tested in production 3 KA3501 Mechanical Dimensions Package Dimensions in millimeters 2.08 ) 0.082 14-DIP 7.62 0.300 3.25 ±0.20 0.128 ±0.008 5.08 MAX 0.200 +0.10 0.25 –0.05 0~15° 4 +0.004 0.010 –0.002 1.50 ±0.10 0.059 ±0.004 #8 2.54 0.100 #7 19.40 ±0.20 0.764 ±0.008 #14 19.80 MAX 0.780 #1 0.46 ±0.10 0.018 ±0.004 ( 6.40 ±0.20 0.252 ±0.008 0.20 0.008 MIN 3.30 ±0.30 0.130 ±0.012 KA3501 Ordering Information Product Number Package Operating Temperature KA3501 14-DIP 0°C ~ +70°C 5 KA3501 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR INTERNATIONAL. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 9/25/00 0.0m 001 Stock#DSxxxxxxxx  2000 Fairchild Semiconductor International