45-V LDO has programmable current limit and power good flag

January 28, 2014 // By Paul Buckley
Linear Technology Corporation has introduced a high voltage, low noise, low dropout voltage linear regulator that offers precision, programmable current limit and a power good flag.

The device delivers up to 500 mA output current with a 300 mV dropout voltage at full load. It features a wide 1.8 V to 45 V input voltage range and output voltage is adjustable from 0.6 V to 40 V. A single REF/BYP pin capacitor provides low noise operation-only 25 µVRMS across a 10 Hz to 100 kHz bandwidth, and also reference soft-start functionality, preventing output voltage overshoot at turn-on. Output voltage tolerance is highly accurate at ±2% over line, load and temperature.

The LT3065 operates with a small, low cost, 3.3 µF ceramic output capacitor, optimizing stability and transient response. The LT3065 PWRGD flag indicates output regulation. One resistor programs the external precision current limit (±10% over temperature). Moreover, the device’s internal protection circuitry includes reverse-battery protection, reverse-output protection, reverse-current protection, current limit with foldback, and thermal limiting.

The device’s wide input and output voltage ranges, fast transient response, low quiescent current of 55 µA (operating) and <1 µA (in shutdown) make it an excellent choice for industrial power supplies, avionic power supplies, automotive power supplies, battery-powered systems and instruments requiring optimum run time, and high reliability power supplies requiring more extensive protection.

Availability and Pricing

The LT3065 is available in thermally enhanced 10-lead 3 mm x 3 mm DFN and 12-lead MSOP packages, both with a compact footprint. The E- and I-grade versions are available from stock with an operating junction temperature of -40°C to +125°C, H grade is rated from -40°C to +150°C, and the MP-grade version is specified from -55 to +150°C. 1,000 piece pricing starts at $1.85 each for the E-grade.

More information about the LT3065 linear regulator at www.linear.com/product/LT3065