The LM2591HV series of regulators are monolithic integrated circuits that provide all the
active functions for a step-down (buck) switching regulator, capable of driving a 1-A load with
excellent line and load regulation. These devices are available in fixed output voltages of 3.3 V,
5 V, and an adjustable output version.
This series of switching regulators is similar to the LM2590HV, but without some of the
supervisory and control features of the latter.
Requiring a minimum number of external components, these regulators are simple to use and
include internal frequency compensation, improved line and load specifications, and a
The LM2591HV operates at a switching frequency of 150 kHz, thus allowing smaller sized
filter components than what would be needed with lower frequency switching regulators. Available in
a standard 5-pin package with several different lead bend options, and a 5-pin surface mount
Other features include a specified ±4% tolerance on output voltage under all conditions
of input voltage and output load conditions, and ±15% on the oscillator frequency. External
shutdown is included, featuring typically 90-µA standby current. Self-protection features include a
two stage current limit for the output switch and an over temperature shutdown for complete
protection under fault conditions.