Semtech SC1109
Synchronous PWM Controller With Dual Low-Dropout Regulator Controllers

Not Recommended for New Designs. Datasheet is for information purposes only.
The SC1109 was designed for the latest high speed motherboards. It combines a synchronous voltage mode controller (switching section) with two low-dropout linear regulator controllers. The voltage mode controller provides the power supply for the system AGTL bus. The Dual linear controllers power the chip set and clock circuitry.Overview
Features
- Dual linear controllers
- LDOs track input voltage within 200 mV (function of the MOSFETs used) until regulation
- Integrated drivers
- Power-good signal (SC1109A, SC1109B)
- Soft start
- Lossless current sense
- Programmable over-current limit (SC1109C)
- Fixed frequency 200 kHz (SC1109A, SC1109C)
- Fixed frequency 500 kHz (SC1109B)
- SO-16 package
Applications
- Pentium® III Motherboards
- Triple power supplies
Packaging
SOIC-16
Order Codes
- SC1109ACSTR: Package Minimum Tape & Reel Only
- SC1109ACSTRT: Lead-Free, RoHS and WEEE Compliant, Package Minimum Tape & Reel Only