RT8207L/M
Complete DDRII/DDRIII/Low-Power DDRIII/DDRIV Memory
General Description
The RT8207L/M provides a complete power supply for both
DDRII/DDRIII/Low-Power DDRIII/DDRIV memory systems.
It integrates a synchronous PWM buck controller with a
1.5A sink/source tracking linear regulator and buffered low
The PWM controller provides the high efficiency, excellent
transient response, and high DC output accuracy needed
for stepping down high voltage batteries to generate low
voltage chipset RAM supplies in notebook computers.
The constant-on-time PWM control scheme handles wide
input/output voltage ratios with ease and provides 100ns
“instant-on” response to load transients while maintaining
The RT8207L/M achieves high efficiency at a reduced cost
by eliminating the current sense resistor found in
traditional current mode PWMs. Efficiency is further
enhanced by its ability to drive very large synchronous
rectifier MOSFETs. The buck conversion allows this device
to directly step down high voltage batteries for the highest
The 1.5A sink/source LDO maintains fast transient
capacitance. In addition, the LDO supply input is available
externally to significantly reduce the total power losses.
The RT8207L/M supports all of the sleep state controls
placing VTT at high-Z in S3 and discharging VDDQ, VTT
The RT8207L/M has all of the protection features including
thermal shutdown and is available in WQFN-24L 4x4 and
Features
Resistor Programmable Current Limit by Low Side
Quick Load Step Response Within 100ns
Fixed 1.8V (DDRII), 1.5V (DDRIII) or Adjustable
DDRIII) and 1.2V (DDRIV)
Resistor Programmable Frequency
Internal Current Limit Ramp Soft-Start
Power Good Indicator
Capable to Sink and Source 1.5A
External Input Available to Minimize Power Losses
and VTTREF
Remote Sensing (VTTSNS)
Supports High-Z in S3 and Soft-Off in S4/S5
Applications
Supplies
SSTL18, SSTL15 and HSTL Bus Termination
Copyright ©2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
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