Power Supply for AMD® 64-Bit SledgeHammer And ClawHammer CPUs
linear.com
MILPITAS, CA – April 2, 2002 – Linear Technology Corporation introduces the LTC3719, a PolyPhase™ synchronous step-down controller with integrated MOSFET drivers designed to power AMD’s new 64-bit Hammer CPUs. The LTC3719 offers a 45A single-chip solution by integrating four MOSFET drivers that are capable of driving substantial gate capacitance. The IC offers two power sections that accurately balance the output power between the power components. This precision current sharing reduces thermal stress increasing the reliability of MOSFETs, inductors & capacitors, facilitates thermal management, eliminates hot spots and the need for heat sinks. Furthermore, PolyPhase operation minimizes the requirement for input and output capacitors. A design using the LTC3719 is compact, cost-effective, highly efficient and offers higher system reliability than competing solutions, which do not have precision current sensing. The IC is housed in a 36-lead SSOP package.
The LTC3719’s 5-bit VID code corresponds to the core voltage range of AMD’s Hammer CPUs. Core voltage range is from 0.8V to 1.55V and core current can range from 15A to 40A. The LTC3719 can deliver this power at up to 95% efficiency from an input voltage source ranging from 4.5V to 36V. The IC’s accurate current sensing typically provides less than 2% IOUT error between the two channels. The LTC3719 includes protection functions such as current foldback, short-circuit shutdown and an overvoltage soft latch.
The LTC3719 is guaranteed for operation from -40°C to 85°C temperature range. Pricing for the 1,000-piece quantity starts at $4.35 each.
Summary of Features: LTC3719
PolyPhase Operation Reduces Input & Output Capacitance Requirement
Precision Load Sharing Eases Thermal Design & Increases System Reliability
5-Bit AMD CPU VID Code: 0.8V to 1.55V Output Voltage Range
±1% Output Voltage Accuracy
True Remote Sensing
The power seems extremely low. Multiplying 1.55V * 40A produces 62 Watts. That is extremely low for the Max power for Hammer. If true, this is a great news about Hammer. It means that Hammer will be lower power processor than Thunderbird, Palomino and Thoroughbred.
Joe |
