L6756
2/3/4 phase buck controller
for VR10, VR11.1 and AM2 processor applications
Data Brief
Features
®
■ LTB technology enhances load transient
response
■ 2 to 4 scalable phase operation
■ Dual-edge asynchronous architecture
■ PSI# input with programmable strategy
■ IMON output
VFQFPN40
■ Flexible driver support
Description
■ 7/8 bit programmable output - VR10/11.x DAC
■ 6 bit programmable output - AMD AM2 DAC
■ 0.5 % output voltage accuracy
L6756 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.
®
■ 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 ouptut
■ Programmable Soft-start
L6756 embeds selectable DAC: Output Voltage is
programmable up to 1.6000 V (Intel VR10 and
VR11.x DACs) or up to 1.550 V (AMD 6bit DAC)
managing DVID transitions with 0.5 % output
voltage accuracy over line, load and temperature
variations.
■ Threshold sensitive enable Pin for VTT
Sensing
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.
■ VFQFPN40 7x7 mm package
Applications
■ High-current VRM / VRD for desktop / server /
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.
workstation CPUs
■ Graphic cards
■ Low-voltage, high-current power supplies
■ High-density DC / DC converters
L6756 is available in VFQFPN40 7x7 mm
package.
Table 1.
Device summary
Order code
Package
Packing
VFQFPN40
VFQFPN40
Tube
L6756
L6756TR
Tape & Reel
February 2008
Rev 1
1/3
For further information contact your local STMicroelectronics sales office.
www.st.com
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