New Industry Products

Linear Tech Dual 500mA Linear LDO Regulator with Independent Inputs Offers Ultralow Noise

February 09, 2010 by Jeff Shepard

Linear Technology Corp. announced the LT3029, a dual low noise, low dropout regulator with independent inputs and independent shutdown control for each channel. The device delivers up to 500mA per channel of continuous output current with a low dropout voltage of only 300mV at full load. The LT3029 features a wide input voltage range of 1.8 to 20V, delivering output voltages as low as 1.215 and up to 19.5V.

The device features ultralow noise of only 20µVRMS across a wide bandwidth of 10Hz to 100kHz, and offers tracking/sequencing capability. Its full feature set and low quiescent current of 55µA per regulator (operating) and <1µA (in shutdown) are said to make it an excellent choice for battery-powered "keep alive" systems that require optimum run time, in addition to microprocessor core logic supplies, tracking/sequencing supplies and general purpose voltage conversion.

The LT3029 operates with very small, low cost, ceramic output capacitors, optimizing stability and transient response. It is stable with only a 3.3µF output capacitor versus older linear regulators that require between 10µF 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, no reverse current flow from output to input, current limiting with foldback and thermal shutdown. The thermal shutdown circuitry protects both channels if an overload or fault condition on either channel occurs.

The LT3029’s compact packages offer thermal resistances equivalent to much larger conventional packages. The LT3029EMSE, LT3029IMSE, LT3029EDE and LT3029IDE are available from stock in a proprietary 16-lead thermally enhanced MSOP package and a 16-lead 4 x 3mm DFN package, with operating junction temperature of -40 to +125°C. The LT3029HMSE and LT3029MPMSE are available and offered in the MSOP package with extended operating junction temperatures of -40 to +150°C and -55 to +125°C, respectively. Pricing starts at $2.87, $3.13, $3.47, and $7.74 each for the E, I, H and MP grades, respectively, in 1,000-piece quantities.