SC1109

SC1109 Synchronous PWM Controller with Dual Low Dropout Regulator Controllers POWER MANAGEMENT Description Features 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. The SC1109A switching section features lossless current sensing, while SC1109C provides programmable over current limit. SC1109 also utilizes latched driver outputs for enhanced noise immunity. SC1109A and SC1109C operate at a fixed frequency of 200kHz, and the SC1109B is available at a fixed frequency of 500kHz. The VTT output voltage is internally fixed at 1.2V The SC1109 linear sections are low dropout regulators designed to track the 3.3V power supply when it turns on or off. The voltage for the linear controllers LDO1, and LDO2 are 1.8V/1...