Description/Applications

The MAX17409 evaluation kit (EV kit) demonstrates the high-power, dynamically adjustable, 1-phase application circuit for NVIDIA® graphics power supplies. This DC-DC converter is intended to either step down high-voltage batteries and/or the 5V system supply, generating a precision, low-voltage CPU core. The MAX17409 EV kit meets the NVIDIA transient voltage specification, power-good signaling, voltage-regulator thermal monitoring (active-low VRHOT), and power-good output (PWRGD). The MAX17409 EV kit includes active voltage positioning with adjustable gain, reducing power dissipation and bulk output-capacitance requirements. An internal amplifier buffers the DAC and accurately controls the slew rate for all output-voltage transitions, including transitions between VID codes, startup, and shutdown. Precision slew-rate control provides just-in time arrival at the new DAC setting, minimizing surge currents to and from the battery.

The MAX17409 includes output undervoltage fault, over-voltage fault, and thermal overload protection. It also includes a voltage-regulator power-good (PWRGD) output.

This fully assembled and tested PCB provides a digitally adjustable 0.3375V to 1.1250V output voltage (6-bit on-board DAC) from a 7V to 24V battery-input range. It delivers up to 14A output current. The EV kit operates at 300kHz switching frequency and has superior line- and load-transient response.