Wide V Range, Low Noise, 250mA Buck-Boost Charge Pump

The LTC3245 is a switched capacitor buck-boost DC/DC converter that produces a regulated output (3.3V, 5V or adjustable) from a 2.7V to 38V input. The device uses switched capacitor fractional conversion to maintain regulation over a wide range of input voltage. Internal circuitry automatically selects the conversion ratio to optimize efficiency as input voltage and load conditions vary. No inductors are required.

The unique constant frequency architecture provides a lower noise output than conventional charge pump regulators. To optimize efficiency at the expense of slightly higher output ripple, the device has pin selectable Burst Mode operation.

Low operating current (20μA with no load, 4μA in shutdown) and low external parts count (three small ceramic capacitors) make the LTC3245 ideally suited for low power, space constrained automotive/industrial applications. The device is short-circuit and overtemperature protected, and is available in thermally enhanced 12-pin MSOP and low profile 3mm × 4mm 12-pin DFN packages.

APPLICATIONS

* Automotive ECU/CAN Transceiver Supplies

* Industrial Housekeeping Supplies

* Low Power 12V to 5V Conversion

* 2.7V to 38V VIN Range

* IQ = 18μA Operating; 4μA in Shutdown

* 12V to 5V Efficiency = 81%

* Multimode Operation (2:1, 1:1, 1:2) with Automatic Mode Switching

* Low Noise, Constant Frequency Operation

* Pin Selectable Burst Mode® Operation