STMicroelectronics PM6641

Description

The PM6641 is a monolithic voltage regulator module specifically designed to supply DDR2/3 memory and chipset in ultra-mobile PC and real estate constrained portable systems.
It integrates three independent, adjustable, constant frequency buck converters, a ±2 Apk Low Drop-Out (LDO) linear regulator and a ±15 mA low noise buffered reference.
Each regulator provides basic UV and OV Protections, programmable Soft-Start and Current Limit and active Soft-End.
Pulse-Skipping technique is performed to increase efficiency at very light load.

Features

■ 0.8 V ±1 % internal voltage reference
■ 2.7 V to 5.5 V input voltage range
■ Fast response, constant frequency, current mode control
■ Three independent, adjustable, out-of-phase SMPS for DDR2/3 (VDDQ) and chipset supply
■ Low noise DDR2/3 reference (VTTREF)
■ ±2 Apk LDO for DDR2/3 termination (VTT) with foldback
■ S0-S5 states compliant DDR2/3 section
■ Active soft-end for all outputs
■ Selectable tracking discharge for VDDQ
■ Separate power-good signals
■ Pulse skipping at light load
■ Programmable current limit and soft-start for all outputs
■ Latched OVP, UVP protection
■ Thermal protection

Applications

■ DDR2/3 memory and chipset supply
■ UMPC and portable equipment
■ Handheld and PDAs