17V, 2A regulator shuts down to 3.5µA quiescent current

April 18, 2014 // By Graham Prophet
LTC3624 is a high efficiency, 17V input capable synchronous buck regulator that delivers up to 2A of continuous output current to outputs as low as 0.6V. Synchronous rectification delivers efficiencies as high as 95% while Burst Mode operation requires only 3.5µA of no load quiescent current.

The LTC3624 switches at a fixed 1MHz frequency, whereas the LTC3624-2 switches at 2.25MHz. Their constant frequency, current-mode architecture minimises switching noise while offering very fast line and load transient response. The LTC3624/-2 operates from an input voltage range of 2.7V to 17V, making it ideal for single cell or multi- cell Li-Ion stack inputs as well as 12V intermediate bus-powered systems. The combination of its 3 x 3 mm DFN package, high switching frequency and tiny, low cost capacitors and inductors ensures a highly compact solution footprint.

The LTC3624/-2’s 60nsec minimum on-time enables it to step-down 16V inputs to 2.5V with a 2.25 MHz switching frequency (LTC3624-2) without pulse skipping, minimising the size of external components thus offering a very compact, high efficiency 2A step-down solution. Its 3.5µA quiescent current suits it for always-on applications demanding maximum battery run time. For applications requiring the lowest possible noise, the LTC3624/-2 can be configured to run in pulse-skipping or forced continuous mode, reducing noise and potential RF interference. Additional features include a power good voltage monitor, internal compensation and thermal protection.

The LTC3624EDD and LTC3624EDD-2 are available in a 3 x 3 mm DFN-8 package, priced at $2.95 (1,000). Industrial grade versions, the LTC3624IDD and the LTC3624IDD-2 are guaranteed to operate over the -40°C to 125°C operating junction temperature range, priced at $3.25.

Linear Technology; www.linear.com/product/LTC3624