45V-input, 100 mA LDO has active output discharge

August 14, 2014 // By Graham Prophet
LT3061 is a high voltage, low noise, low dropout voltage linear regulator with active output discharge. The device delivers up to 100 mA of continuous output current with a 250 mV dropout voltage at full load.

The LT3061 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 in high-end imaging sensors.

The LT3061 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 LT3061's output voltage tolerance is accurate at ±2% over line, load and temperature. The device’s wide input and output voltage range, fast transient response, low quiescent current of 45 µA (operating) and less than 2 µA (in shutdown) suit it for portable battery-powered systems that require optimum run time, and for use in automotive, industrial and avionic power supply applications.

The LT3061 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 LT3061 is housed in thermally enhanced 8-lead 2 x 3 mm DFN and MSOP packages. E- and I-grade versions feature an operating junction temperature of -40°C to +125°C, the high reliability H-grade is specified from -40°C to +150°C and the military MP-grade operates from -55°C to +150°C. Pricing is from $1.55 (1000).

Linear Technology; www.linear.com/product/LT3061