Linear Technology Introduces the LTC1871 Controller

Linear Technology Corp. (Milpitas, CA) announced the new LTC1871, a wide-input-range, current-mode, boost, flyback and SEPIC controller that drives an n-channel power MOSFET and requires very 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.

The IC’s operating frequency can be set with an external resistor over a 50kHz to 1MHz range, and can be synchronized to an external clock using the MODE/SYNC pin. Burst-mode operation at light loads, a low minimum operating supply voltage of 2.5V and a low shutdown quiescent current of 10µA make the LTC1871 suitable for use in battery-operated systems.

For applications requiring constant frequency operation, the burst-mode operation feature can be defeated using the MODE/SYNC pin. Higher-output voltage boost, SEPIC and flyback applications are possible with the LTC1871 by connecting the SENSE pin to a resistor in the source of the power MOSFET.

The LTC1871 is available in the 10-lead MSOP package.