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

The LTC7811 is a high performance triple output (buck/buck/boost) 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 LTC7811 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 LTC7811 can operate from an input supply as low as 1V after start-up.

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 LTC7811 features a precision 0.8V reference for the bucks, 1.2V reference for the boost and a power good output indicator.

The LTC7811 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 Synchronous Buck Plus Single Boost 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 Output Voltages Up to 40V

* Boost Output Voltage Limited Only by External Components

* Spread Spectrum Operation