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Preliminary Specification describes products that are not in full production at the time of printing. Specifications are based on design goals and
limited characterization. They may change without notice. Contact Fairchild Semiconductor for current information.
P
www.fairchildsemi.com
Pentium is a registered trademark of Intel Corporation
Rev. 1.1.6
Features
Programmable output from 1.3V to 3.5V using an
integrated 5-bit DAC
Remote sense
Active Droop
85% efficiency typical at full load
Integrated Power Good and Enable/Soft Start functions
Drives N-channel MOSFETs
Overcurrent protection using MOSFET sensing
20 pin SOIC package
Meets Intel Pentium II specifications using minimum
number of external components
Adjustable deadtime, frequency
Crowbar protection for overvoltage
Applications
Power supply for Pentium
VRM for Pentium II & III processor
Telecom line cards
Routers, switches & hubs
Programmable step-down power supply
II & III
Description
The RC5052 is a synchronous mode DC-DC controller IC
which provides a highly accurate, programmable output voltage
for all Pentium II & III CPU applications and other high-perfor-
mance processors. The RC5052 features remote voltage
sensing, adjustable current limit, and active droop for optimal
converter transient response. The RC5052 uses a 5-bit D/A
converter to program the output voltage from 1.3V to 3.5V.
The RC5052 uses a high level of integration to deliver load
currents in excess of 16A from a 5V source with minimal
external circuitry. Synchronous-mode operation offers opti-
mum efficiency over the entire specified output voltage range.
An on-board precision low TC reference achieves tight toler-
ance voltage regulation without expensive external components,
while active droop permits exact tailoring of voltage for the
most demanding load transients. The RC5052 also offers
integrated functions including Power Good, Output Enable/
Soft Start, current limiting, adjustable frequency, adjustable
deadtime and overvoltage crowbar protection, and is available
in a 20 pin SOIC package.
Block Diagram
2
VID0
VID1
GNDP
9
10
8
OVP
7
13
4
11
12
3
-
+
-
+
OSC
1.24V
Reference
Digital
Control
5-Bit
DAC
VID2
VID3
VID4
2019181716
+5V
+12V
PWRGD
-
+
ENABLE/SS
VO
GNDA
14
LODRV
HIDRV
VCCQP
R
S
6
15
1
VCCA
DTA
+5V
5
+
-
Power
Good
Rosc
RC5052
High Performanc e Programmable S ync hronous
DC-DC Controller for Low Voltage Mic roproc essors