40V, Low I, 3MHz, Triple Output Buck/Buck/Boost Synchronous Controller

The LTC7818 is a high performance triple output (buck/buck/boost) synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Its constant-frequency current mode architecture allows a phase-lockable switching frequency of up to 3MHz. The LTC7818 operates from a wide 4.5V to 40V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC7818 can operate from an input supply as low as 1V after start-up.

The LTC7818 synchronous boost PassThru capability minimizes losses in automotive start-stop applications. The very low 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 LTC7818 features a precision 0.8V reference for the bucks, 1.2V reference for the boost and a power good output indicator.

The LTC7818 additionally features spread spectrum operation which significantly reduces the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interference (EMI) standards.

APPLICATIONS

* Automotive and Transportation

* Industrial

* Military/Avionics

* Dual Buck Plus Single Boost Synchronous Controllers

* Low Operating IQ: 14μA (14V to 3.3V, Channel 1 On)

* Outputs Remain in Regulation Through Cold Crank Down to 1V Input Supply Voltage

* Wide Bias Input Voltage Range: 4.5V to 40V

* Buck and Boost Output Voltages up to 40V

* Spread Spectrum Operation

* RSENSE or DCR Current Sensing