BL8542B Datasheet | BELLING

BL8542B REV1.2, DEC 2010 0.85V startup, 1MHz, 300m A Iout, Synchronous Boost Converter DESCRIPTION The BL8542B is a step-up converter that provides a boosted output voltage from a low voltage source. Because of its proprietary design, it starts up at a very low input voltage down to 850m V, making it an ideal choice for single cell alkaline/Ni MH battery operations. A switching frequency of 1MHz minimizes solution footprint by allowing the use of tiny, low profile inductors and ceramic capacitors. The current mode PWM design is internally pensated, reducing external parts count. BL8542B is housed in a tiny SOT23-5 and SOT89-3 Package. TYPICAL APPLICATION CIRCUIT Features - - Up to 95% Efficiency - - Output voltage accuracy 3％ - - 1MHz Switching Frequency allows small inductor and output cap - - Input boost-strapping allows using small or no input cap - - Low Vin Start-up Voltage down to 850m V Ideal for Single Alkaline Cell operations - - Maximum Output Current up to 300m A - - Low Noise PWM control - - Internally pensated Current Mode Control - - Internal Synchronous Rectifier - - Logic Control Shutdown (IQ<1u A) APPLICATIONS - - One to Three Cell Battery Operated Devices - - Medical Instruments - - Bluetooth Headsets - - Flash-Based MP3 Players - - Noise Canceling Headphones PIN CONFIGURATION NOTE: Input capacitor (Cin=0.47u F) and Output capacitor (Cout≥4.7u F) are remended in all application circuit. ORDERING INFORMATION Product BL8542B-ADJ BL8542B-3.3V BL8542B-5.0V Product Code BL8542BCB5TR...