LTC389x Synchronous DC/DC Controllers Analog Devices Inc. LTC389x Synchronous Controllers are high-performance step-down switching regulator DC/DC controllers. The LTC389x controllers, with the exception of the LTC3894 series, drive all N-channel synchronous power MOSFET stages. The MOSFET stage can operate from input voltages up to 150V. The high-voltage LTC3894 Controllers drive a P-channel power MOSFET switch. LTC389x's constant-frequency, current-mode architecture achieves up to an 850kHz phase-lockable frequency. Designers can program the gate drive voltage from 5V to 10V. This programming enables the use of standard-level or logic FETs for maximum efficiency. Using external resistors, designers can also program the output voltage from 0.8V to 60V. Pin-programming allows for a fixed 5V or 3.3V output voltage.