LM22673

LM22673 3A SIMPLE SWITCHER®, Step-Down Voltage Regulator with Adjustable Soft-Start and Current Limit November 5, 2008 LM22673 3A SIMPLE SWITCHER®, Step-Down Voltage Regulator www.datasheet4u.com with Adjustable Soft-Start and Current Limit General Description The LM22673 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 3A 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 LM22673 series also has built in thermal shutdown and current limiting. The current limit threshold can be adjusted using an external resistor. An adjustable soft-start feature is provided by selecting an appropriate external soft-start capacitor. Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Wide input voltage range: 4.5V to 42V Internally compensated voltage mode control Stable with low ESR ceramic c...