IRDC3891: 1.8V @ 4A, 1.2V @ 4A, 12Vin, Dual buck

The IR3891 is a dual synchronous buck converter, providing a compact, high performance and flexible solution in a small 5mm X 6mm Power QFN package.

Key features offered by the IR3891 include internal Digital Soft Start, precision 0.5V reference voltage, Power Good, thermal protection, programmable switching frequency, Enable input, input under-voltage lockout for proper start-up, enhanced line/load regulation with feed forward, external frequency synchronization with smooth clocking, internal LDO, pre-bias start-up, output over voltage protection as well as open feedback line protection.

Output over-current protection function is implemented by sensing the voltage developed across the on-resistance of the synchronous rectifier MOSFET for optimum cost and performance and the current limit is thermally compensated.

This user guide contains the schematic and bill of materials for the IRDC3891 evaluation board. The guide describes operation and use of the evaluation board itself. Detailed application information for IR3891 is available in the IR3891 data sheet.