Dual 550kHz Synchronous 2-Phase Switching Regulator Controller

The LTC1702 is a dual switching regulator controller optimized for high efficiency with low input voltages. It includes two complete, on-chip, independent switching regulator controllers each designed to drive a pair of external N-channel MOSFET devices in a voltage mode feedback, synchronous buck configuration. The LTC1702 uses a constant-frequency, true PWM design switching at 550kHz, minimizing external component size and cost and maximizing load transient performance. The synchronous buck architecture automatically shifts to discontinuous and then to Burst Mode™ operation as the output load decreases, ensuring maximum efficiency over a wide range of load currents.

The LTC1702 features an onboard reference trimmed to 0.5% and can provide better than 1% regulation at the converter outputs. Open-drain logic outputs indicate whether either output has risen to within 5% of the final output voltage and an optional latching FAULT mode protects the load if the output rises 15% above the intended voltage. Each channel can be enabled independently; with both channels disabled, the LTC1702 shuts down and supply current drops below 100µA.

Applications

* Microprocessor Core and I/O Supplies

* Multiple Logic Supply Generator

* Distributed Power Applications

* High Efficiency Power Conversion

* Two Independent Controllers in One Package

* Two Sides Run Out-of-Phase to Minimize CIN

* All N-Channel External MOSFET Architecture

* No External Current Sense Resistors

* Excellent Output Regulation: 1% Total Output Accuracy

* 550kHz Switching Frequency Minimizes External Component Size

* 1A to 25A Output Current per Channel

* High Efficiency over Wide Load Current Range

* Quiescent Current Drops Below 100µA in Shutdown

* Small 24-Pin Narrow SSOP Package