Linear Technology Announces Surface Mount 500mA LDO

Linear Technology Corporation has announced the LT3085, the member of a family of NPN LDOs that can be paralleled for heat spreading and are adjustable down to "0" volts with a single resistor. This architecture regulator uses a current reference rather than a conventional voltage reference to allow sharing between multiple regulators by directly paralleling the pins. Current sharing is set with a small length of PC trace as ballast, enabling multi-amp linear regulation in all surface-mount systems without heat sinks. The LT3085 achieves without any compromises. Featuring 500mA output current and wide input voltage capability from 1.2V to 36V, it has a low dropout voltage of only 275mV at full load. The output voltage is adjustable, spanning a wide range from 0V to 35V, and the on-chip trimmed current reference achieves an accuracy of ±1%. The wide VIN and VOUT capability, low external parts count and parallel capability make it ideal for modern multirail systems. Output voltage noise is a low 33uVrms over a wide bandwidth of 10Hz to 100kHz. Protection features include current limiting with foldback and thermal limiting.



The LT3085 is offered in two high power density packages: the low profile (0.75mm) 6-lead DFN (2mm x 3mm) and 8-pin thermally enhanced MSOP. These packages can dissipate 1W to 2W in surface mount applications without a heat sink. The LT3085E and LT3085I feature an operating junction temperature of -40°C to +125°C, while the LT3085MP (MSOP package only) features operation down to -55°C junction temperature. 1,000 piece pricing starts at $1.73 and $1.90 for the DFN package in E and I grades respectively, and at $1.83, $2.00 and $4.94 for the MSOP package E, I and MP grades, respectively.