45V-in, 200-mA LDO with active output discharge

June 20, 2014 // By Graham Prophet
LT3063 is a high voltage, low noise, low dropout voltage linear regulator with active output discharge. The IC delivers up to 200 mA of continuous output current with a 300 mV dropout voltage at full load.

The part includes an internal NMOS pull-down that discharges the output voltage if either the SHDN pin is driven low or the input voltage is turned off. This rapid output discharge helps protect the load in applications requiring power conditioning on both start-up and shutdown, such as high-end imaging sensors.

LT3063 features a 1.6V to 45V input voltage range and delivers adjustable output voltages from 0.6V to 19V. A single capacitor provides programmable ultralow noise operation, only 30 µVRMS across a 10 Hz to 100 kHz bandwidth and reference soft-start functionality, preventing output voltage overshoot at turn-on. The LT3063's output voltage tolerance is accurate at ±2% over line, load and temperature. The device’s input and output voltage range, fast transient response, low quiescent current of 45 µA (operating) and <3 µA (in shutdown) suit it for portable battery-powered systems that require optimum run time, and for usage in automotive, industrial and avionic power supply applications.

It operates with a small, low cost, ceramic output capacitor, optimising stability and transient response. The IC is stable with a minimum value 3.3 µF output capacitor. The device’s internal protection circuitry includes reverse-battery protection, reverse-current protection, current limit with foldback and thermal limiting.

The device is housed in thermally enhanced 8-lead 2 x 3 mm DFN and MSOP packages, in several temperature ranges. Pricing starts at $1.67 (1000).

Linear Technology; www.linear.com/product/LT3063