LTC Intros LTC3731H PolyPhase DC-DC Controller

Linear Technology Corp. (LTC, Milpitas, CA) introduced its new LTC3731H, a PolyPhase® step-down, synchronous controller with operation and precision for junction temperatures as high as 140 °C. The dc-dc controller has integrated MOSFET drivers and is expandable from 3-phase to 12-phase operation for 60 A to 240 A power supply designs. Applications for the LTC3731H range from high-end notebook PCs to embedded systems and single-board computers for industrial, instrumentation, telecom and medical systems, as well as automotive, heavy equipment and high power industrial systems.

The accuracy of the reference voltage is high, with ±2% accuracy over the entire operating temperature range. The ±5% output current simplifies thermal management by evenly spreading the heat among the output stages. Housed in a narrow, 36-lead SSOP (5.3 mm wide), the LTC3731H is a single-IC solution for high-output distributed power in systems requiring dc-dc conversion from a 4.5 V to 32 V input source to 0.6 V to 6 V output in buck mode. The LTC3731H configured as three-phase boost converter delivers high output currents with low output ripple.

The LTC3731H incorporates a patented power-saving Stage Shedding™ technique to optimize efficiency and improve battery life at light loads by eliminating the gate charging losses and switching losses of two of its output stages. The PolyPhase operation reduces input ripple current and improves transient response as well as minimizing the requirement for input and output capacitors. The IC operates from 250 kHz to 600 kHz per phase to achieve an optimal frequency for efficiency, ease of thermal design and use of small inductors and capacitors. To protect the load and MOSFETs, the LTC3731H is equipped with short-circuit and overload protection as well as soft-start to protect the system from high inrush current.

The LTC3731H is offered in a 36-lead SSOP. Pricing for 1,000-piece quantities starts at $5.00 each.