42V Synchronous Step-Down Silent Switcher with Ultralow EMI/EMC Emissions

Analog Devices, which recently acquired Linear Technology, announces the LT8609S, a 2A (3A Peak), 42V input synchronous step-down switching regulator. Its unique Silent Switcher 2 architecture uses two internal input capacitors as well as internal BST and INTVCC capacitors to minimize the area of the hot loops.

The LT8609S design dramatically reduces EMI/EMC emissions due to very well controlled switching edges, it’s internal construction with an integral ground plane and the use of copper pillars in lieu of bond wires. This improved EMI/EMC performance is not sensitive to board layout, simplifying design and reducing risk even when using two-layer PC boards. The LT8609S easily pass the automotive CISPR 25, Class 5 peak EMI limits with a 2MHz switching frequency over its entire load range. Spread spectrum frequency modulation is available to lower EMI/EMC levels further.

The LT8609S’s synchronous rectification delivers efficiency as high as 93% with a switching frequency of 2MHz. The LT8609S’s Burst Mode operation offers only 2.5μA of quiescent current, well suited for applications such as automotive always-on systems, needed to extend operating battery life (more info).