SC4508A
SC4508A is Buck or Buck-Boost Current Mode Controller manufactured by SEMTECH.
Buck or Buck-Boost (Inverting) Current Mode Controller
POWER MANAGEMENT Description
The SC4508A is a low voltage current mode switching regulator controller that drives a P-channel power MOSFET with programmable switching frequency. It can be configured in either buck or buck boost (inverting) converters. The converters can be operated from 2.7V to 15V input voltage range. The typical operating supply current is 3m A and a shutdown pin allows the user to turn the controller off reducing it to less than 200µA. The output voltage can adjusted by external resistor di.. vider. The switching frequency is programmable up to 1.5MHz, allowing small inductor and capacitor values to minimize PCB space. The operating current level is programmable via an external sense resistor. Accessible reference voltage allows users to make output voltage as low as they want.
Features
Wide input voltage range 2.7V to 15V Programmable output voltage Programmable switching frequency up to 1.5MHz Buck or buck boost (inverting) configuration Current mode control with slope pensation Very low quiescent current in shutdown mode Accessible reference voltage Hiccup mode after 32 cycle-by-cycle OCP 4mm x 4mm MLPQ-12 lead free package. This product is fully WEEE and Ro HS pliant
Applications
Low power point of use converters Single or multiple output low power converters Positive and/or negative output voltage DSL cards Graphic cards I/O cards Negative bias supplies
Typical Application Circuits
Vin Vin
V+ V+ VREF VREF CS FB+ OUT FB-
FB+ FB-
Vout SS/EN GND OSC
Vout SS/EN GND OSC
Revision: July 25, 2007
.semtech.
POWER MANAGEMENT...
