POWER MANAGEMENT
Description
The SC454 is a single-phase chip, high-performance PWM
controller designed to power advanced IMVP-6 and IMVP6+
™ processors. On-chip support is provided for all of the
IMVP-6/6+ requirements, including Active Voltage Position-
ing, Geyserville-3 VID transitions, VID-Controlled Deeper
Sleep voltage setting, PSI#, DPRSTP#, DPRSLP Control,
Fast and Slow C4 Exit, and default Boot Voltage.
The SC454 implements hysteretic control technology which
provides the fastest possible transient response while
avoiding the stability issues inherent to classical PWM
controllers. Eliminating the sense resistors reduces costs
and PCB area, plus increases system efficiency. Integrated
SmartDriver™ technology initially turns on the high-side
driver with ‘soft’ drive to reduce ringing, EMI, and capaci-
tive turn-on of the low side MOSFET, while also increasing
overall efficiency.
Hysteretic operation adaptively reduces the SC454 switch-
ing frequency at light loads. Combined with an automatic
“power-save” mode which prevents negative current
fl
ow in
the low-side FET, system efficiency is significantly enhanced
during light loading conditions.
A 7-bit DAC, accurate to 0.85%, sets the output voltage
reference, and implements the 0.300V to 1.500V range
required by the processor. The DAC slew rate is externally
programmed to minimize transient currents and audible
noise. True differential remote sensing provides accurate
point-of-load regulation at the processor die. Other features
include programmable soft-start, open-drain IMVP-6/6+
PWRGD and CLKEN# outputs, dynamic current sharing,
over-voltage and programmable over-current protection.
The SC454 is available in a space-saving 32-pin MLP
package.
Single-Phase Single Chip
IMVP-6/6+ Vcore Power Supply
Features
Single-Phase Solution with Integrated Drivers
Hysteretic Control for Fast Transient Response
VR_TT Support
Active Voltage Positioning
True Differential Remote (die) Sensing
On-Chip Support for all IMVP-6/6+ Power
Management Features
VID Programmed Deeper Sleep Voltage
Fast/Slow C4E Break Event Support
Clock Enable (CLKEN#) Output
Delayed Power Good Signal with Blanking
Programmable Soft-Start and DAC Slew Control
Programmable OCP Threshold
Supports all Ceramic Decoupling Solutions
32-pin MLP (5x5)
Latched Over-Voltage Protection
SC454
Applications
IMVP-6/6+ Notebook PCs
Embedded Applications
March 20, 2006
1
www.semtech.com
Industrial Control Electronics
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