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SC1474
Portable Pentium
®
Dual Phase
Power Supply Controller
POWER MANAGEMENT
Revision 6, December 2002
Description Features
Applications
Typical Application Circuit
IMVP3 compliant single chip solution
High speed Dual phase hysteretic controller
VID programmable output
Dual integrated 2A/4A drivers
Integrated VID regulator controller
Automatic performance/battery mode detection
Dynamic phase current matching
Under-voltage lock out on all Vcc inputs
Over-voltage protection on CORE
Current Limit protection on CORE
Thermal protection
Programmable soft-start
Powergood flag with blanking during VID changes
Automatic powersave at light load
TSSOP-38 package
Industrial temperature range
The SC1474 PowerStep III™ IC is a single chip high-per-
formance Hysteretic PWM controller. With dual integrated
Smart™ Drivers, it powers advanced Pentium® 4 pro-
cessors. The SC1474 features extended Intel Mobile Volt-
age Positioning (IMVP) to increase battery life by reduc-
ing the voltage at the processor when it is heavily loaded.
It directly supports Intel’s SpeedStep™ requirements for
even longer battery life. The SC1474 automatically de-
tects performance and battery mode VIDs. In addition, it
integrates direct “deeper sleep” mode support. All op-
erating modes incorporate automatic “power-save” to
prevent negative current flow in the low-side FET during
light loading conditions, saving even more power.
A 5-bit DAC, accurate to 0.85%, sets the output voltage
reference, and implements the 0.600V to 1.750V range
required by the processor. The hysteretic converter uses
a comparator without an error amplifier, and so provides
the fastest possible transient response, while avoiding
the stability issues inherent to classical PWM controllers.
The SC1474 incorporates a controller for V_VID and au-
tomatically provides the proper sequencing.
The SC1474 operates from +3.3Vdc Vcca and dual 5V
DC drive inputs. It also features soft-start, an open-drain
PWRGD signal with power-good blanking, and an enable
input. Programmable current limiting latches the SC1474
off after 32 current limit pulses. It comes in a space-
saving TSSOP-38 package.
Advanced Intel microprocessors
SC1474
Dual Phase
Extended IMVP
CONTROLLER
VID [4:0]
Lo
+VCORE
+V_IN
+V_5
0.600V-1.75V
Up to 40A
Extended
IMVP
Logic
Controller
Power
Control
Signals
Smart
Driver
VID
Multiplexer
Lo
Co
Smart
Driver
Rcs
Rcs
+V_3
+V_VID
VID
Regulator
Controller
SC1474
Dual Phase
Extended IMVP
CONTROLLER
VID [4:0]
Lo
+VCORE
+V_IN
+V_5
0.600V-1.75V
Up to 40A
Extended
IMVP
Logic
Controller
Power
Control
Signals
Smart
Driver
VID
Multiplexer
Lo
Co
Smart
Driver
Rcs
Rcs
+V_3
+V_VID
VID
Regulator
Controller
