SP6127

SP6127 High-Voltage, Step-Down Controller in TSOT6 FEATURES W ide 4.5V – 29V Input Voltage Range Internal compensation Built-in High-Current PMOS Driver Adjustable Overcurrent Protection Internal soft start 900kHz Constant Frequency Operation 0.6V Reference Voltage 1% output setpoint accuracy Lead Free, RoHS Compliant Package: Small 6-pin TSOT LX GND FB 6 5 4 SP6127 6 PinTSOT 1 VIN 2 GATE 3 VDR __________________________________________________________ DESCRIPTION The SP6127 is a PWM controlled step down (buck) voltage mode regulator with VIN feedforward and internal Type-II compensation. It operates from 4.5V to 29V VIN, making it suitable for 5V, 12V and 24V applications. By using a PMOS driver, this device is capable of operating at 100% duty cycle. The highside driver is designed to drive the gate 5V below VIN. The programmable overcurrent protection is based on the high-side MOSFET’s ON resistance sensing and allows setting the overcurrent protection value up to 300mV threshold (measured between VIN-LX). The SP6127 is available in a space-saving 6pin TSOT package making it the smallest controller available capable of operating from 24VDC supplies. _______________________________________ TYPICAL APPLICATION CIRCUIT VIN Q1 Si2343DS 2 1 Vin Rs=1k LX C7 0.1uF 6 L1, IHLP-2525CZ 3.3uH, 30mOhm, 6A Gate C1 4.7uF 12V GND VOUT C4 22uF R1 200k, 1% 4 CZ 33pF R2 100k, 1% D1 1N4148 SP6127 3 VDR Ds MBRA340T3G RZ 2K 1.8V 0-2.0A VFB GND 5 SHDN H igh=Of f GND Jan28-08 RevE SP6127 TSOT-6 PFET Buck Controller Page 1  2007 Exar Corporation ABSOLUTE MAXIMUM RATINGS These are stress ratings only, and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Input Voltage….................................................-0.3V to 30V Lx………………………………………………….…-2V to 30V FB……………..................................................-0.3V to 5.5V Storage Temperature..………………...……-65 °C to 150 °C Junction Temperature...................................-40°C to 125°C Lead Temperature (Soldering, 10 sec)…..…………..300 °C ESD Rating………..….…1kV LX, 2kV all other nodes, HBM Specifications are for TAMB=TJ=25°C, and those denoted by ♦ apply over the full operating range, -40°C< Tj