FAN5029_07 Datasheet, PDF (1/3 Pages) Fairchild Semiconductor – 8-Bit Programmable 2- to 5-Phase Synchronous Buck Controller

January 2007
FAN5029
8-Bit Programmable 2- to 5-Phase Synchronous Buck Controller
Features
• Selectable 2-, 3-, 4-, or 5-phase operation at up to
1MHz per phase
• ±7.7mV worst-case differential sensing error
• Active current balancing between the output phases
• Power good and crowbar blanking supports on-the-
fly VID code changes
• Selectable VR10 extended (7-bit) and VR11 (8-bit)
VID tables
• Programmable short-circuit protection and latch-off
delay
• Programmable soft start ramp
Applications
• Desktop PC/Server processor power supplies for
existing and next generation Intel processors
• VRM modules products
Part Numbers
• FAN5029MPX is not for new designs.
• The FAN5029MPX_NAAC238 replaces the
FAN5029MPX and is compatible with all VR10 and
VR11 processors.
Description
The FAN5029 is a multi-phase buck switching
regulator controller optimized to convert a 12V input
supply to the processor core voltage required by high-
performance Intel® processors. It has an internal 8-bit
DAC that converts a digital voltage identification (VID)
code that is sent from the processor to set the output
voltage between 0.5V and 1.6V. It outputs a PWM to
external MOSFET drivers that, in turn, drive the
switching power MOSFETs. The switching frequency
of the design is programmable by a single resistor
value and the number of phases can be programmed
to support 2-, 3-, 4-, or 5-phase applications.
The FAN5029 also includes programmable no-load
offset and droop functions to adjust the output voltage
as a function of the load current, as required by the
Intel specifications. The FAN5029 also provides an
accurate and reliable short-circuit protection function
with an adjustable over-current set point.
The FAN5029 is specified over the extended
commercial temperature range of 0°C to +85°C and is
available in a 40-lead MLP package.
Ordering Information
Part Number
FAN5029MPX
FAN5029MPX_NAAC238
Temperature
Range
0°C to 85°C
Package
Type
Lead
Free
Packing Method
MLP-40
Not For New Designs
Yes
Tape and Reel
For more information, please contact Ron Berthiaume at [e-mail].
Quantity
per Reel
3,000
© 2004 Fairchild Semiconductor Corporation
FAN5029 Rev. 1.1.3
www.fairchildsemi.com