LT3487

The LT®3487 dual channel switching regulator generates positive and negative outputs for biasing CCD imagers. The device delivers up to 8V at 90mA and 15V at 45mA from a lithium-ion cell, providing bias for many popular CCD imagers. The boost regulator of LT3487 incorporates output disconnect technology to eliminate the DC current path from V_IN to the output load that is present in standard boost confi gurations. The 2MHz switching frequency allows CCD solutions using tiny, low profi le capacitors and inductors and generates low noise outputs that are easy to fi lter. Schottky diodes are internal and the output voltages are set with one resistor per channel, reducing the external component count.

Intelligent soft-start of LT3487 allows sequential soft-start of the two channels with a single capacitor. The soft-start is sequenced such that the output ramp of the negative channel begins after the ramp of the positive channel. Internal sequencing circuitry also disables the negative channel until the positive channel has reached 87% of its fi nal value, ensuring that the sum of the two outputs is always positive.

The LT3487 is available in a 10-pin 3mm * 3mm DFN package.