The MAX17028/MAX17428 are 1-phase Quick-PWM™ step-down VID power-supply controllers for Intel® notebook CPUs. The Quick-PWM control provides instantaneous response to fast load current steps. Active voltage positioning reduces power dissipation and bulk output capacitance requirements and allows ideal positioning compensation for tantalum, polymer, or ceramic bulk output capacitors.

The MAX17028/MAX17428 are intended for two different notebook CPU/GPU core applications: either bucking down the battery directly to create the core voltage, or else bucking down the +5V system supply. The single-stage conversion method allows these devices to directly step down high-voltage batteries for the highest possible efficiency. Alternatively, 2-stage conversion (stepping down the +5V system supply instead of the battery) at higher switching frequency provides the minimum possible physical size.

A slew-rate controller allows controlled transitions between VID codes. A thermistor-based temperature sensor provides programmable thermal protection. A current monitor provides an analog output current proportional to the processor load current.

The MAX17028/MAX17428 implement both the Intel IMVP-6.5 CPU core specifications (V3P3 = 3.3V), as well as the Intel GMCH graphics core specifications (V3P3 = GND). The MAX17028/MAX17428 are available in a 32-pin, 5mm x 5mm, TQFN package.

Applications

• 1-to-4 Lithium-Ion (Li+) Cell Battery-to-CPU Core
• Graphics Core Power Supply
• IMVP-6.5 Core Power Supply
• Intel Calpella Platforms
• Intel GMCH 2009
• Notebooks/Desktops/Servers
• Supply Converters
• Voltage-Positioned Step-Down Converters