SEMTECH SC472B

SC472B
Single-Phase Single Chip
Graphics Core Power Supply
POWER MANAGEMENT
Description
Features
The SC472B is a single-phase chip, high-performance
PWM controller designed to power advanced graphic cores.
On-chip support is provided for all of the Intel® integrated
requirements, including Active Voltage Positioning, Slewrate controlled VID transitions, and VID-Controlled Sleep
voltage settings.
Single-Phase Solution with Integrated Drivers
Hysteretic Control for Fast Transient Response
Active Voltage Positioning
True Differential Remote (die) Sensing
On-Chip Support for all IMVP-6+ Graphics Power Management Features
VID Programmed Deeper Sleep Voltage
Delayed Power Good Signal with Blanking
Programmable Soft-Start and DAC Slew Control
Programmable OCP Threshold
Supports all Ceramic Decoupling Solutions
24-Pin MLP (4x4)
Lead-Free Package. This product is fully WEEE and RoHS compliant.
The SC472B 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 capacitive turn-on of the low side MOSFET, while also increasing
overall efficiency.
Applications
Hysteretic operation adaptively reduces the SC472B
switching frequency at light loads. Combined with an automatic “powersave” mode which prevents negative current
flow in the low-side FET, system efficiency is significantly
enhanced during light loading conditions.
IMVP-6+ Notebook Graphic Cores
Embedded Applications
A 5-bit DAC, accurate to 0.85%, sets the output voltage
reference, and implements the voltage 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, an open-drain PWRGD output,
dual-level over-voltage and programmable over-current
protection. The SC472B is available in a space-saving
4x4mm, 24-pin MLP package.
Updated - Apr 10, 2007
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