The 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 reduces EMI/EMC emissions due to very well controlled switching edges, its 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 2 MHz 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 2 MHz. Its 3.0V to 42V input voltage range is suitable for automotive and industrial applications. The internal high efficiency switches deliver up to 2A of continuous output current and peak loads of 3A to voltages as low as 0.774V. The LT8609S’s Burst Mode operation offers 2.5 µA of quiescent current, for applications such as automotive always-on systems, needed to extend operating battery life. The LT8609S’s unique design maintains a minimum dropout voltage of 400 mV (at 1.5A) under all conditions, for scenarios such as automotive cold crank. A fast minimum on-time of only 45 nsec enables 2 MHz constant frequency,
for more detail: 2-3A, 42-Vin Silent Switcher offers low-EMI regulation