1545CS Datasheet | SEMTECH

DESCRIPTION The SC1545 was designed for instantly available motherboard applications. As part of the Semtech family of Smart LDO’s it provides additional control functions not available in a standard LDO. The device provides the capability to control three separate supplies. There is an on-board 500m A, 2.5V LDO with current limit protection, and drive pins for an N-channel MOSFET and a P-channel MOSFET. Internal logic circuitry ensures that the system starts up in a controlled manner, and that the correct outputs are enabled during specific sequences of BF_CUT and SLP. The LDO draws its power from the 5V standby supply, and the N-channel MOSFET drive is derived from the 12V supply. The SC1545 is available in the surface mount SO-8 package. Features - - - 500m A LDO with Over Current Protection (OCP) ±2.5% LDO regulation over line, load and temperature Power sequencing for three supplies APPLICATIONS - - - Instantly available motherboards Embedded systems Desktop puters ORDERING INFORMATION Part Number SC1545CS (1) Package SO-8 Note: (1) Add suffix ‘TR’ for tape and reel packaging. TYPICAL APPLICATION CIRCUIT 2.5V IN Q1 2.5V OUT Si4410 C1 2 x 100u F C2 100u F 3.3V IN Q2 3.3V OUT IRLMS6802 C3 2 x 100u F C4 100u F U1 1 2.5V OUT 2 3 4 C5 10u F VO GND PDR NDR SC1545 5VSTBY 12VIN BF_CUT SLP 8 7 6 5 C6 1u F C7 0.1u F 5V STANDBY 12V IN BF_CUT SLP 1 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 .. 500m A Smart LDO With Power Up Signal Sequencing PRELIMINARY - January 17, 2000 SC1545 ABSOLUTE MAXIMUM RATINGS Parameter 12V Input Voltage Range 5V Input Voltage Range P-channel MOSFET Gate Drive N-channel MOSFET Gate Drive Input Pins Operating Ambient Temperature Range Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 Sec Thermal Impedance Junction to Case Thermal Impedance Junction to Ambient ESD Rating Note: (1) 2 inch square of 1/16” FR-4, double sided, 1 oz. minimum copper weight. (1) Symbol 12VIN 5VSTBY PDR...