PM6670 Datasheet, PDF (1/53 Pages) STMicroelectronics – Complete DDR2/3 memory power supply controller

PM6670
Complete DDR2/3 memory power supply controller
Preliminary Data
Features switching
■ Switching section (VDDQ)
– 4.5V to 28V input voltage range
– 0.9V, ±1% voltage reference
– 1.8V (DDR2) or 1.5V (DDR3) fixed output
voltages
– 0.9V to 2.6V adjustable output voltage
– 1.237V ±1% reference voltage available
– Very fast load transient response using
constant on-time control loop
– No R_SENSE current sensing using low side
MOSFET’s R_DS(ON)
– Negative current limit
– Latched OVP and UVP
– Soft start internally fixed at 3ms
– Selectable pulse skipping at light load
– Selectable No-Audible (33KHz) pulse skip
mode
– Ceramic output capacitors supported
– Output voltage ripple compensation
■ VTT LDO and VTTREF
– 2Apk LDO with foldback for VTT
– Remote VTT sensing
– High-Z VTT output in S3
– Ceramic output capacitors supported
– ±15mA Low noise buffered reference
Applications
■ DDR2/3 memory supply
■ Notebook computers
■ Handheld and PDAs
■ CPU and chipset I/O supplies
■ SSTL18, SSTL15 and HSTL bus termination
VFQFPN-24 4x4
Description
The device PM6670 is a complete DDR2/3 power
supply regulator designed to meet JEDEC
specifications.
It integrates a Constant On-Time (C.O.T.) buck
controller, a 2Apk sink/source Low Drop Out
regulator and a 15mA low noise buffered
reference.
The C.O.T. architecture assures fast transient
response supporting both electrolytic and ceramic
output capacitors. An embedded integrator
control loop compensates the DC voltage error
due to the output ripple.
The 2Apk sink/source linear regulator provides
the memory termination voltage with fast load
transient response.
The device is fully compliant with system sleep
states S3 and S4/S5, providing LDO output high
impedance in Suspend-To-RAM and Tracking
Discharge of all outputs in Suspend-To-Disk.
Table 1. Device summary
Part number
PM6670
Package
VFQFPN-24 4x4 (Exposed Pad)
Packaging
Tube
March 2007
Rev 1
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to
change without notice.
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