LM22671EVAL: 3.3V @ 500mA, 4.5 ~ 42Vin

Summary

The LM22671 series of regulators are monolithic integrated circuits which provide all of the active functions for a step-down (buck) switching regulator capable of driving up to 500 mA loads with excellent line and load regulation characteristics. High efficiency (>90%) is obtained through the use of a low ON-resistance N-channel MOSFET. The series consists of a fixed 5V output and an adjustable version.

The switching clock frequency is provided by an internal fixed frequency oscillator which operates at 500 kHz. The switching frequency can also be adjusted with an external resistor or synchronized to an external clock up to 1 MHz. It is also possible to self-synchronize multiple regulators to share the same switching frequency.

The LM22671 series also has built in thermal shutdown, current limiting and an enable control input that can power down the regulator to a low 25 µA quiescent current standby condition. An adjustable soft-start feature is provided by selecting an appropriate external soft-start capacitor.

Specifications

Manufacturer	Texas Instruments
Category	AC/DC and DC/DC Conversion
Sub-Category	DC/DC SMPS - Single Output
Eval Board Part Number	LM22671EVAL/NOPB-ND
Eval Board Supplier	Texas Instruments
Eval Board	Normally In Stock
Topology	Step Down
Outputs and Type	1 Non-Isolated
Voltage Out: Factory Set	3.3 V
Current Out	500 mA
Voltage In	4.5 ~ 42 V
Efficiency @ Conditions	>87%, 5.5V in, 3.3V @ 100 ~ 500 mA >83%, 12V in, 3.3V @ 200 ~ 500 mA >61%, 40V in, 3.3V @ 200 ~ 500 mA
Voltage Out Range	1.285 ~ 37 V
Features	Current Limit (Adj. or Fixed) Shutdown, Enable, Standby Soft Start Synchronizable Thermal Protection
Switching Frequency	500 kHz
Standby Current [Typical]	25 µA
Quiescent Current [Typical]	3.4 mA
Component Count + Extras	10 + 4
Internal Switch	Yes
Design Author	Texas Instruments
Application / Target Market	Automotive Point of Load (PoL) Telecom
Standby Current [Maximum]	40 µA
Quiescent Current [Maximum]	6 mA
Main I.C. Base Part	LM22671
Date Created By Author
Date Added To Library	2011-03