SP6125

SP6125 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 300kHz 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 SP6125 6 PinTSOT 1 VIN 2 GATE 3 VDR DESCRIPTION The SP6125 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, making is suitable for 5V, 12V, and 24V applications. By using a PMOS driver, this device is capable of operating at 100% duty cycle. The high side driver is designed to drive the gate 5V below VIN. The programmable overcurrent protection is based on high-side MOSFET’s ON resistance sensing and allows setting the overcurrent protection value up to 300mV threshold (measured from VIN-LX). The SP6125 is available in a space-saving 6-pin TSOT package making it the smallest controller available capable of operating from 24VDC supplies. TYPICAL APPLICATION CIRCUIT VIN Q1 FDS4685 C1 4.7uF C2 4.7uF 24V 2 1 Vin Rs 2k LX C6 0.1uF 6 Gate GND L1, IHLP-2525CZ 8.2uH, 68mOhm, 4A VOUT C4 22uF R1 300k, 1% C5 22uF SP6125 3 VDR 4 VFB GND 5 Ds MBRA340T3G RZ 2K 3.3V 0-3A CZ 47pF R2 66.5k, 1% D1 1N4148 GND SHDN H igh=Of f Jan28-08 RevG SP6125: TSOT-6 PFET Buck Controller  2007 Exar Corporation 1 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, 1…0 sec)….…………..300 °C ESD Rating……….…….…1kV LX, 2kV all other nodes, HBM ELECTRICAL SPECIFICATIONS Specifications are for TAMB=TJ=25°C, and those denoted by ♦ apply over the full operating range, -40°C< Tj