Linear Technology Corp.’s LTC6909 precision silicon oscillator significantly reduces peak radiated EMI and improves control of switching regulators in multiphase power supplies. The LTC6909 has eight separate outputs, providing up to eight rail-to-rail 50 percent duty cycle clock signals. These outputs can be used to enable or disable and phase-synchronize multiple switching regulators. Using three logic inputs, the phase relationship between these outputs can be configured from 45° to 120°, or the outputs can be placed in a logic low or high-Z state. A single resistor selects the output frequency from 12.5kHz to 6.67MHz. The LTC6909 also offers spread spectrum frequency modulation (SSFM), a technique that modulates the clock frequency by a pseudorandom signal.
Fully specified over the temperature range of -40°C to 125°C, the LTC6909 offers rugged and reliable operation, as well as fast startup and low power consumption.
Linear Technology Corp.
