MAX8686

19-4113; Rev 0; 5/08 www.DataSheet4U.com Single/Multiphase, Step-Down, DC-DC Converter Delivers Up to 25A Per Phase General Description The MAX8686 current-mode, synchronous PWM stepdown regulator with integrated MOSFETs operates from a 4.5V to 20V input supply and generates an adjustable output voltage from 0.7V to 5.5V while delivering up to 25A per phase. The MAX8686 employs a peak current-mode architecture that operates with an adjustable switching frequency from 300kHz to 1MHz. An adjustable current-limit threshold allows for optimization for different applications with different load currents. Inductor current sense is achieved either using an external sense resistor or using a lossless inductor current-sense scheme. The foldback and hiccup current limit reduces the power dissipation during overload or short-circuit conditions and allows for autorecovery when the fault condition is removed. The MAX8686 offers the ability to start up monotonically even when there is a prebias output voltage. In addition, an adjustable soft-start capability allows for a controlled turn-on. The MAX8686 features an accurate 1% reference and offers a reference input that allows for a higher accuracy reference to be used for voltage tracking applications such as DDR memory. The MAX8686 can be paralleled (up to eight) together in a true multiphase mode to deliver up to 200A of output current. When operating in this mode, this device achieves better than 10% current balance between phases at ...