LM22678

LM22678 5A SIMPLE SWITCHER®, Step-Down Voltage Regulator with Precision Enable October 17, 2008 LM22678 5A SIMPLE SWITCHER®, Step-Down Voltage Regulator www.datasheet4u.com with Precision Enable General Description The LM22678 series of regulators are monolithic integrated circuits which provide all of the active functions for a stepdown (buck) switching regulator capable of driving up to 5A 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 SIMPLE SWITCHER® concept provides for an easy to use complete design using a minimum number of external components and National’s WEBENCH® design tool. National’s WEBENCH® tool includes features such as external component calculation, electrical simulation, thermal simulation, and Build-It boards for easy design-in. The switching clock frequency is provided by an internal fixed frequency oscillator which operates at 500 kHz. The LM22678 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. Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Wide input voltage range: 4.5V to 42V Internally compensated voltage mode control Stable with low ESR ceramic capacitors 100 mΩ N-channel MOSFET Output voltage options: -ADJ (outputs as low as 1.285V) -5.0 (output fixed to 5V...