150V Low I, Synchronous Inverting DC/DC Controller

The LTC3896 is a high performance inverting DC/DC switching regulator controller that drives an all N-channel synchronous power MOSFET stage. It converts a wideranging positive input voltage source to a regulated negative output that can be as much as 60V below ground. The input can operate from a voltage as low as 4V and as high as 140V – |VOUT–|.

The LTC3896 contains true ground-referenced RUN, PLLIN and PGOOD pins, eliminating the need for external discrete level-shifting components to interface with the LTC3896.

A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. The low 40μA no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3896 features a precision 0.8V reference and power good output indicator. The soft-start (SS) pin ramps the output voltage during start-up.

Applications

* Automotive and Industrial Power Systems

* Telecommunications Power Supplies

* Distributed Power Systems

* Wide VIN + |VOUT–| Range: 4V to 140V (150V Abs Max)* Wide Output Voltage Range: –60V to –0.8V* Ground-Referenced Control / Interface Pins* Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)* Integrated Bootstrap Diode* Low Operating IQ: 40μA (Shutdown = 10μA)* Selectable Gate Drive UVLO Thresholds* Onboard LDO or External NMOS LDO for DRVCC* EXTVCC LDO Powers Drivers from Output* Phase-Lockable Frequency (75kHz to 850kHz)* Programmable Fixed Frequency (50kHz to 900kHz)* Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads* Adjustable Burst Clamp and Current Limit* Power Good Output Voltage Monitor* Programmable Input Overvoltage Lockout* 38-Lead TSSOP High Voltage Package