L6756D Datasheet, PDF (1/36 Pages) STMicroelectronics – 2/3/4 phase buck controller for VR10, VR11 and VR11.1 processor applications

L6756D
2/3/4 phase buck controller
for VR10, VR11 and VR11.1 processor applications
Features
■ LTB Technology^® enhances load transient
response
■ 2 to 4 scalable phase operation
■ Dual-edge asynchronous architecture
■ PSI# input with programmable strategy
■ Imon output
■ Flexible driver support
■ 7/8 bit programmable output - VR10/11.1 DAC
■ 0.5% output voltage accuracy
■ Full-differential current sense across DCR
■ Integrated remote sense buffer
■ Feedback disconnection protection
■ Adjustable oscillator from 100 kHz to 1 MHz
■ LSLess startup to manage pre-biased output
■ Programmable soft-start
■ Threshold sensitive enable pin for VTT
Sensing
■ VFQFPN40 6x6 mm package
Applications
■ High-current VRM / VRD for desktop / server /
workstation CPUs
■ Graphic cards
■ Low-voltage, high-current power supplies
■ High-density DC / DC converters
VFQFPN40 6x6 mm
Description
L6756D is a two-to-four phase controller designed
to power Intel’s most demanding processors and,
most in general, low-voltage, high-current power
supplies. The device features LTB Technology^® to
provide the fastest response to load transients
thus minimizing the output
filter composition.
L6756D embeds selectable DAC: output voltage
is programmable up to 1.6000 V (Intel VR10 and
VR11.x DACs) managing DVID transitions with
±0.5% output voltage accuracy over line, load and
temperature variations.
The device assures fast protection against load
over current and under / over voltage. Feedback
disconnection prevents from damaging the load in
case of misconnections in the system board.
Low-side-less start-up allows soft-start over pre-
biased output avoiding dangerous current return
through the main inductors as well as negative
spike at the load side.
L6756D is available in VFQFPN 6x6 mm package
Table 1.
Device summary
Order code
L6756D
L6756DTR
Package
VFQFPN40
VFQFPN40
Packing
Tube
Tape and reel
October 2008
Rev 1
1/36
www.st.com
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