The LTC3815 from Linear Technology Corporation is a 6 A monolithic synchronous step-down DC/DC converter with an I²C-based PMBus interface for digital power system management (PSM). The PMBus digital interface provides programming and read back of voltage, current, temperature and faults, all supported by LTpowerPlay software. This interface allows the output voltage to be margined over a ±25% range with 0.1% resolution. The default output voltage is set with a single external resistor and will power up to this voltage with or without the serial interface.
The LTC3815 accepts inputs from 2.25 V to 5.5 V, suiting it for operation from 2.5 V, 3.3 V or 5 V rails or from lithium-ion batteries. The output voltage is programmable from 0.4 V to 72% of VIN or can be set with an external voltage reference, making it ideal for intelligent energy power conversion, ASIC/FPGA power, distributed power and point-of-load applications.
A phase-lockable controlled on-time, current mode architecture gives the converter extremely fast transient response and enables operation at the low duty cycles necessary to regulate low output voltages at high switching frequencies. The operating frequency is programmable from 400 kHz to 3 MHz with an external resistor or for switching noise sensitive applications. It can be synchronized to an external clock over the same range.
An integrated differential amplifier provides true remote output voltage sensing enabling high accuracy regulation, independent of board IR voltage drops. Additional features include a clock output for 2-phase operation, a power good signal, selectable forced continuous or discontinuous mode and 1 ms start-up time.
The LTC3815 is available in a 38-lead 4mm x 6mm QFN package with an operating junction temperature range of -40°C to 125°C. The 1,000-piece price starts at $4.71 each.