Linear Tech Micropower 50mA Linear Regulator Withstands 80V Input
Linear Technology Corp. announced the LT3011, a high voltage micropower, low dropout regulator that delivers up to 50mA of continuous output current with a low dropout voltage of only 300mV at full load. The LT3011 features an input voltage range of 3 to 80V, delivering output voltages as low as 1.24V and up to 60V.
The device’s PowerGood flag indicates output regulation. However, a single capacitor may be used to program the delay between this regulated output level and the flag indication. The 80V input voltage capability makes it suitable for automotive applications, 48V telecom backup supplies and industrial control applications. Low quiescent current of 46uA (operating) and 1µA (in shutdown) make it a suitable choice for battery-powered "keep alive" systems that require optimum run time.
Output noise is minimized at only 100µVRMS over a 10Hz to 100kHz bandwidth, making the LT3011 suitable for noise-sensitive applications. According to the company, for high voltage applications that require large input-to-output voltage differentials, the LT3011 provides a very compact solution. Its thermally enhanced MSOP and DFN packages are said to offer thermal resistance equivalent to much larger conventional packages.
The company claims that the LT3011 is able to operate with very small, low cost, ceramic output capacitors. It is stable with only a 1µF output capacitor while older linear regulators require between 10 and 100µF to maintain stability. These tiny external capacitors can be used without the necessary addition of series resistance (ESR) as is common with many other regulators. Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting, and no reverse current flow from output to input.
The LT3011E and LT3011I are available from stock in a proprietary 12-lead thermally enhanced MSOP package and a 10-lead 3 x 3mm DFN package, both with operating junction temperature of -40 to +125°C. The LT3011H is available in the MSOP package only and is rated up to +150°C operating junction temperature. Pricing starts at $1.75, $1.93 and $2.26 each for the E, I and H grades, respectively, in 1,000-piece quantities.
