The MAX17039 is a dual-output, step-down, constant-on-time controller for VR12/IMVP7 CPU core supplies. The controller consists of two high-current-switching power supplies for the CPU and GPU cores. The CPU regulator (regulator A) is a three-phase constant-on-time architecture. The optional third phase is configured with an external MAX17491 driver. The second GPU regulator (regulator B) is also a constant-on-time architecture with only single phase.Both regulators A and B include true differential voltage and current sensing to improve load-line and current-limit accuracy. Switching frequencies are independently programmable, allowing 100kHz to 600kHz per phase operation. Output overvoltage protection (OVP), undervoltage protection (UVP), and thermal protection ensure effective and highly reliable operation. When any of these protection features detect a fault, the controller shuts down both channels.Regulator A includes transient-phase overlap, which speeds up the response time, reducing the total output capacitance. It also includes active overshoot suppression to further reduce the required output decoupling capacitance.The CPU and GPU outputs are controlled independently by writing the appropriate data into a function mapped register file. A slew-rate controller allows controlled transitions between VID codes with controlled soft-start. The SVID interface also allows each regulator to be individually set into a low-power pulse-skipping state. Individual phases can be shut down based on the processors’ operating conditions to optimize efficiency. The MAX17039 is available in a lead-free, 56-pin, 7mm x 7mm TQFN package.ApplicationsNotebooks/Desktops/ServersVoltage-Positioned Step-Down ConvertersVR12/IMVP7 CPU Core Power Supplies