The operating frequency is externally programmable up to 4MHz, allowing the use of small surface mount inductors. 0, 90, or 180 of phase shift between the two channels can be selected to minimize input current ripple and output voltage ripple in a single 6A output configuration. Programmable slew rate limiting reduces EMI, and external synchronization can be applied up to 4MHz. The internal synchronous switches increase efficiency and eliminate the need for external catch diodes, saving external components and board space. The LTC3615 is offered in leadless 24-pin 4mm x 4mm QFN and thermally enhanced 24-pin TSSOP packages.