SG1842 Datasheet | Linfinity

L I N D O C # : 1842 SG1842/SG1843 Series CURRENT MODE PWM CONTROLLER N F I N I T E N N O VA T I O N R O D U C T I O N DESCRIPTION The SG1842/43 family of control IC's provides all the necessary Features to implement off-line fixed frequency, current-mode switching power supplies with a minimum number of external ponents. Current-mode architecture demonstrates improved line regulation, improved load regulation, pulse-by-pulse current limiting and inherent protection of the power supply output switch. The bandgap reference is trimmed to ±1% over temperature. Oscillator discharge current is trimmed to less than ±10%. The SG1842/43 has undervoltage lockout, current limiting circuitry and start-up current of less than 1m A. The totem-pole output is optimized to drive the gate of a power MOSFET. The output is low in the off state to provide direct interface to an N channel device. The SG1842/43 is specified for operation over the full military ambient temperature range of -55°C to 125°C. The SG2842/43 is specified for the industrial range of -25°C to 85°C, and the SG3842/43 is designed for the mercial range of 0°C to 70°C. K E Y F E AT U R E S s OPTIMIZED FOR OFF-LINE CONTROL s LOW START-UP CURRENT (<1m A) s AUTOMATIC FEED FORWARD PENSATION s TRIMMED OSCILLATOR DISCHARGE CURRENT s PULSE-BY-PULSE CURRENT LIMITING s ENHANCED LOAD RESPONSE CHARACTERISTICS s UNDER-VOLTAGE LOCKOUT WITH 6V HYSTERESIS (SG1842 only) s DOUBLE-PULSE SUPPRESSION s HIGH-CURRENT TOTEM-POLE OUTPUT (1AMP PEAK) s INTERNALLY TRIMMED BANDGAP REFERENCE s 500KHZ OPERATION s UNDERVOLTAGE LOCKOUT SG1842 - 16 volts SG1843 - 8.4 volts s LOW SHOOT-THROUGH CURRENT <75m A OVER TEMPERATURE PRODUCT HIGHLIGHT T Y P I C A L A P P L I C AT I O N S G 3 8 4 2 I N A F LY B A C K C O N V E R T E R HIGH RELIABILITY Features s AVAILABLE TO MIL-STD-883B AND DESC SMD s SCHEDULED FOR MIL-M38510 QPL LISTING s RADIATION DATA AVAILABLE s LINFINITY...