LM2672N-ADJ

The LM2672 series of regulators are monolithi cintegrated circuits built with a LMDMOS process.These regulators provide all the active functions for astep-down (buck) switchin regulator,capable of driving a 1A load current with excellent line and load regulation.These devices are avail- able in fixed output voltages of 3.3V,5.0V,12V,and an adjustable output version.

Requiring a minimum number of external components,these regulators are simple to use and include patented internal frequency compensation(Patent Nos.5,382,918 and 5,514,947)and a fixed frequency oscillator.

The LM2672 series operates at a switching frequency of 260kHz,thus allowing smaller sizedfilter components than what would be needed with lower frequency switching regu-
lators.Because of its very high efficiency (>90%),the cop- pe rtraces on the printed circuit board are the only heat sinking needed.

A family of standard inductors for use with the LM2672 are available from severa ldifferent manufacturers.This feature greatly simplifies the design of switch-mode power supplies using these advanced ICs.Also included in the datasheet are selector guides for diodes and capacitors designed to workin switch-mode power supplies.

Other features include a guaranteed ±1.5%tolerance on output voltage within specified input voltages and output 10%on the oscillator frequency.Ex- ternal shutdown is included,featuring typically 50 A stand-by current.The output switch includes current limiting, as well as thermal shutdown for fullprotection under fault conditions.

To simplify the LM2672 buck regulator design procedure, there exists computer design software, LM267X Made Simple version 1.0.