The LT3668 400-mA, 40V step-down switching regulator with a user-programmable switching frequency from 250 kHz to 2.2 MHz integrates dual tracking LDO outputs in its 16-lead MSOP. Targeting applications that require the power supply of a sensor to tightly track the supply of a measurement ASIC, the device operates from a VIN range of 4.3V to 40V with transient protection to 60V. Its internal 600mA switch can deliver up to 400mA, which is distributed to the combined loads of the primary output and both of the tracking LDOs. The primary switching channel can deliver outputs as low as 1.2V, and each LDO can deliver outputs as low as 1.1V. Additionally, the LT3668 requires only 50µA of quiescent current when all three channels are in regulation. The LT3668EMSE is available in a thermally enhanced 16-lead MSOP package priced at $2.55 each/1,000 while the LT3668IMSE with a -40°C to +125°C operating junction temperature is $2.81 each/1,000. A datasheet is available at http://www.linear.com/product/LT3668
Linear Technology Corp.