The ISL8277MEVAL1Z and ISL8278MEVAL1Z evaluation boards are 3in x 4.5in 4-layer FR4 boards with 2 oz. of copper in all layers. These boards come with a placeholder for pin-strap resistors to adjust output voltage, switching frequency, input undervoltage (UVLO) protection threshold, and the device PMBus address. More configurations, such as soft-start and fault limits, can be easily programmed or changed using a PMBus compliant serial bus interface.
The ISLUSBEVAL1Z (USB to PMBus adapter) is provided with these boards, which connects the evaluation boards 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 ISL8277M (25A) and ISL8278M (33A) are step-down DC/DC power supply modules with an integrated digital PWM controller, synchronous power switches, an inductor, and passives. Only bulk input and output capacitors are needed to finish the design. The 25A and 33A of continuous output current can be delivered without the need for airflow or a heatsink. Both devices use ChargeMode™ control architecture, which responds to a transient load within a single switching cycle.
- VIN range of 4.5V to 14V, VOUT adjustable from 0.6V to 5V
- Programmable VOUT, margining, UV/OV, IOUT limit, soft-start/stop, sequencing, and external synchronization
- Monitor: VIN, VOUT, IOUT, temperature, duty cycle, switching frequency, and faults
- ChargeMode control tunable with PMBus
- Mechanical switch for enable and power-good LED indicator
- Servers, telecom, storage, and datacom
- Industrial/ATE and networking equipment
- General purpose power for ASIC, FPGA, DSP, and memory