National Semiconductor LM22679
The LM22679 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. 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.GENERAL DESCRIPTION
High efficiency (>90%) is obtained through the use of a low ON-resistance N-channel MOSFET. 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 LM22679 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
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● 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) ±1.5% feedback reference accuracy Switching frequency of 500kHz -40°C to 125°C operating junction...