Flyback and SEPIC controller eliminates the need for a current sense resistor

Linear Technology’s new LTC1871X is a wide input range, current mode, boost, flyback or SEPIC controller that drives an N-channel power MOSFET and requires few external components. Intended for low to medium power applications, it eliminates the need for a current sense resistor by utilizing the power MOSFET’s on-resistance, thereby maximizing efficiency. The device’s design is optimized for high temperature environments up to 175°C. It’s 2.5V to 36V input voltage range is ideal for high temperature applications such as oil exploration drilling equipment with power sources ranging from 3V to 36V. The electrical parameters are 100% tested at 175°C, offering a VREF accuracy of ±2% over the entire –40C to 175C temperature range. The flexibility for use in boost, SEPIC or flyback topologies is ideal for a wide range of battery-powered applications commonly found in downhole drilling applications. The device’s Burst Mode operation offers low quiescent current, well suited for applications that require extended operating battery life. Specialized Cu/Ni/Au bond pad plating ensures long life in high temperature environments while a tiny MSOP-10 package offers a highly compact solution footprint.