PM6670S Datasheet, PDF (1/53 Pages) STMicroelectronics – Complete DDR2/3 memory power supply controller

PM6670S
Complete DDR2/3 memory power supply controller
Features
■ Switching section (VDDQ)
– 4.5 V to 28 V input voltage range
– 0.9 V, ±1 % voltage reference
– 1.8 V (DDR2) or 1.5 V (DDR3) fixed output
voltages
– 0.9 V to 2.6 V adjustable output voltage
– 1.237 V ±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 3 ms
– Selectable pulse skipping at light load
– Selectable No-Audible (33 kHz) pulse skip
mode
– Ceramic output capacitors supported
– Output voltage ripple compensation
■ VTT LDO and VTTREF
– 2 Apk LDO with foldback for VTT
– Remote VTT sensing
– High-Z VTT output in S3
– Ceramic output capacitors supported
– ±15 mA 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
Table 1. Device summary
VFQFPN-24 4x4
Description
The device PM6670S is a complete DDR2/3
power supply regulator designed to meet JEDEC
specifications.
It integrates a Constant On-Time (COT) buck
controller, a 2 Apk sink/source Low Drop Out
regulator and a 15 mA low noise buffered
reference.
The COT 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 2 Apk 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.
Part number
Package
Packaging
PM6670S
PM6670STR
VFQFPN-24 4x4 (Exposed pad)
Tube
Tape and reel
February 2008
Rev 1
1/53
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