LTC Intros LTC3809-1 Synchronous DC-DC Controller

Linear Technology Corp. (LTC, Milpitas, CA) introduced the LTC3809-1, a No RSENSE synchronous step-down dc-dc controller in a 3 mm x 3 mm DFN-10 (or MSOPE-10) package. The controller's 550 kHz frequency and current-mode architecture with MOSFET VDS sensing eliminates the need for a current-sense resistor while delivering efficiencies as high as 95 percent. The LTC3809-1's input-voltage range of 2.75 V to 9.8 V makes it suitable for single or dual lithium-ion, or multi-cell nickel-metal hydride/nickel-cadmium/alkaline battery applications, as well as standard 3.3 V and 5 V rails to operate in Burst Mode® with only 100 µA of quiescent current.

The LTC3809-1 offers a user-adjustable, tracking/soft-start input that smoothly ramps the output voltage during startup. Other features include default internal soft-start circuitry, an auxiliary winding regulation, and output over-voltage protection.

The LTC3809EDD-1 and LTC3809EMSE-1 are both available from stock in 3 mm x 3 mm DFN-10 and MSOPE-10 packages, respectively. Pricing starts at $2.50 each in 1,000-piece quantities.