Wide VRange Buck-Boost Charge Pump with Watchdog Timer

The LTC3246 is a switched capacitor buck-boost DC/DC converter with integrated watchdog timer. The device produces a regulated output (3.3V, 5V or adjustable) from a 2.7V to 38V input. Switched capacitor fractional conversion is used 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 LTC3246’s reset time and watchdog timeout may be set without external components, or adjusted using external capacitors. A windowed watchdog function is used for high reliability applications. The reset input can be used for additional supply monitoring or be configured as a pushbutton reset.

Low operating current (20μA without load, 1.5μA in shutdown) and low external parts count make the LTC3246 ideally suited for low power, space constrained automotive/ industrial applications. The device is short-circuit and overtemperature protected and is available in a thermally enhanced 16-pin MSOP package.

Applications

* Automotive ECU/CAN Transceiver Supplies

* Industrial/Telecom Housekeeping Supplies

* Low Power 12V to 5V Conversion

* 2.7V – 38V Operating Range (42V Abs Max)* IQ = 20μA Operating, 1.5μA in Shutdown* Multi-Mode Buck-Boost Charge Pump (2:1, 1:1, 1:2) with Automatic Mode Switching* 12V to 5V Efficiency = 81%* IOUT Up to 500mA* VOUT: Fixed 3.3V, 5V or Adjustable (2.5V to 5V)* Ultralow EMI Emissions* Engineered for Diagnostic Coverage in ISO 26262 Systems* Overtemperature, Overvoltage and Short Circuit Protection* Operating Junction Temperature: 150°C Max* POR/Watchdog Controller w/External Timing Control* Thermally Enhanced 16-Pin MSOP Package