30A/30A Dual-Channel Digital PMBus Step-Down Power Module Evaluation Board

The ISL8274MEVAL1Z provides all of the circuitry required to evaluate the features of the ISL8274M 30A/30A dual-channel digital PMBus™ step-down power module. A majority of the features of the ISL8274M, such as compensation-free ChargeMode™ control, soft-start delay and ramp times, supply sequencing, and voltage margining are available on this evaluation board. For sequencing evaluation, the board can be connected to any digital module evaluation board that supports the Digital-DC™ (DDC) bus.

The ISL8274M is a dual-channel, step-down DC/DC power supply module capable of delivering up to 30A per channel. With an integrated digital PWM controller, synchronous power switches, an inductor, and passives, only input and output capacitors are needed to finish the design. A set of optional external resistors allows the user to easily configure the device for standard operation. For advanced configurations, a standard PMBus interface addresses tasks such as sequencing and fault management, as well as real-time full telemetry and point-of-load (POL) monitoring.

The ISL8274M uses ChargeMode control architecture, which responds to a transient load within a single switching cycle. Operating across an input voltage range from 4.5V to 14V, the ISL8274M offers adjustable output voltage from 0.6V to 5V.

The ISL8274MEVAL1Z evaluation board is a 4in x 4.5in 8-layer FR4 board with 2oz. copper on the top and bottom layers and 1oz. copper in the buried layers. This evaluation board comes with a placeholder for pin-strap resistors to adjust the output voltage, switching frequency, input undervoltage lockout (UVLO) protection threshold, device PMBus address, overcurrent limit, ASCR setting, and soft-start setting. More configurations can be easily programmed or changed using a PMBus compliant serial bus interface.

The ISLUSBEVAL1Z (USB to PMBus adapter) is provided with this evaluation board, which connects the evaluation board to a PC to activate the PMBus communication interface. The PMBus command set is accessed by using the PowerNavigator™ evaluation software from a PC running Microsoft Windows. The ISL8274MEVAL1Z can operate in pin-strap mode without needing the ISLUSBEVAL1Z adapter or PMBus communication.