SM645

SM645/SM646/SM647 SWITCHING REGULATOR POWER OUTPUT STAGES DESCRIPTION FEATURES The SM645/646/647 series of Power Output Stages are especially designed to be driven with standard PWM integrated circuits to form an efficient switching power supply. The SM645, SM646 and SM647 are optimized for non-isolated Buck and Buck-Boost application. The hybrid circuit construction utilizes thick film resistors on a beryllia substrate for maximum thermal conductivity and resultant low thermal impedance. All of the active elements in the hybrid are fully passivated. Equivalent to the Unitrode PIC 645, 646, 647 15A current capability Cost saving design reduces size, improves efficiency, reduces noise and RFI High operating frequency (to > 100KHz) results in smaller inductor-capacitor filter and improved power supply response time High operating efficiency at 7A typical performance - Rise and fall time < 300ns Efficiency > 85% HIGH RELIABILITY FEATURES ♦ Available with high reliability processing FUNCTIONAL DIAGRAM SM645/SM646/SM647 4/90 Rev 1.1 2/94 Copyright © 1994 LINFINITY Microelectronics Inc. 1 11861 Western Avenue ∞ Garden Grove, CA 92841 (714) 898-8121 ∞ FAX: (714) 893-2570 SM645/SM646/SM647 ABSOLUTE MAXIMUM RATINGS (Note 1) SM645 SM646 SM647 Input Voltage, V4 - 2 ......................................... Output Voltage, V1 - 2 ...................................... Drive Input Reverse Voltage, V ................ 3-4 Continuous Output Current, I1 .................