LTC Announces LTC3776 Switching Regulator Controller
Linear Technology Corp. (LTC, Milpitas, CA) announced its new LTC3776, a two-phase, dual-output, synchronous step-down, switching regulator controller for DDR/QDR memory termination applications. The second output of the controller regulates its output voltage to one-half of VREF (usually VDDQ) while providing symmetrical source and sink output current capability.
The LTC3776 operates from an input range of 2.75 V to 9.8 V, enabling it to operate from 3.3 V input rails without any external biasing. A no-RSENSE, constant-frequency, current-mode architecture eliminates the need for sense resistors while improving efficiency. Power losses and switching noise due to input capacitance ESR are minimized by operating the two controllers out of phase.
The LTC3776’s switching frequency can be programmed up to 750 kHz, enabling the use of small, surface-mount inductors and capacitors. For noise-sensitive applications, the LTC3776’s switching frequency can be externally synchronized from 250 kHz to 850 kHz with phase-lock-loop circuitry, or spread spectrum operation can be enabled.
The LTC3776EUF and LTC3776EGN are both available from stock in 4 mm x 4 mm QFN-24 and SSOP-24 packages, respectively. Pricing starts at $3.75 each for both the LTC3776EUF and the LTC3776EGN, in 1,000-piece quantities.
