LM2596 Datasheet | National Semiconductor

Description The LM2596 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, and an adjustable output version. Requiring a minimum number of external ponents, these regulators are simple to use and include internal frequency pensation†, and a fixed-frequency oscillator. The LM2596 series operates at a switching frequency of 150 k Hz thus allowing smaller sized filter ponents than what would be needed with lower frequency switching regulators. Available in a standard 5-lead TO-220 package with several different lead bend options, and a 5-lead TO-263 surface mount package. A standard series of inductors are available from several different manufacturers optimized for use with the LM2596 series. This feature greatly simplifies the design of switch-mode power supplies. Other features include a guaranteed ± 4% tolerance on output voltage under specified input voltage and output load conditions, and ± 15% on the oscillator frequency. External shutdown is included, featuring typically 80 µA standby current. Self protection features include a two stage frequency reducing current limit for the output switch and an over temperature shutdown for plete protection under fault conditions. Features n 3.3V, 5V, 12V, and adjustable output versions n Adjustable version output voltage range, 1.2V to 37V ± 4% max over line and load conditions n Available in TO-220 and TO-263 packages n Guaranteed 3A output load current n Input voltage range up to 40V n Requires only 4 external ponents n Excellent line and load regulation specifications n 150 k Hz fixed frequency internal oscillator n TTL shutdown capability n Low power standby mode, IQ typically 80 µA n High efficiency n Uses readily available standard inductors n Thermal shutdown and current limit protection Appli...