SC488中文資料SEMTECH數(shù)據(jù)手冊PDF規(guī)格書

Description

The SC488 is a combination switching regulator and linear source/sink regulator intended for DDR1/2 memory systems. The purpose of the switching regulator is to generate the supply voltage, VDDQ, for the memory system. It is a pseudo-fixed frequency constant on-time controller designed for high efficiency, superior DC accuracy, and fast transient response. The purpose of the linear source/sink regulator is to generate the memory termination voltage, VTT, with the ability to source and sink 2.8A peak currents.

Features

? Constant On-Time Controller for Fast Dynamic Response on VDDQ

? DDR1/DDR2/DDR3 Compatible

? VDDQ = Fixed 1.8V or 2.5V, or Adjustable From 1.5V to 3.0V

? 1.5 Internal Reference (2.5 System Accuracy)

? Resistor Programmable On-Time for VDDQ

? VCCA/VDDP Range = 4.5V to 5.5V

? VIN Range = 2.5V to 25V

? VDDQ DC Current Sense Using Low-Side RDS(ON) Sensing

? External RSENSE in Series with Low-Side FET

? Cycle-by-Cycle Current Limit for VDDQ

? Digital Soft-Start for VDDQ

? Analog Soft-Start for VTT/REF

? Smart Over-Voltage VDDQ Protection

? Combined EN and PSAVE Pin for VDDQ

? Over-Voltage/Under-Voltage Fault Protection

? Power Good Output

? Separate VCCA and VDDP Supplies

? VTT/REF Range = 0.75V – 1.5V

? VTT Source/Sink 2.8A Peak

? Internal Resistor Divider for VTT/REF

? VTT is High Impedance in S3

? VDDQ, VTT, REF are Actively Discharged in S4/S5

? 24 Lead MLPQ (4x4 mm) Lead-Free Package

? Product Is Fully WEEE and RoHS Compliant

Applications

? Notebook Computers

? CPU I/O Supplies

? Handheld Terminals and PDAs

? LCD Monitors

? Network Power Supplies