On Sat, 09 Feb 2013 08:44:00 +1100, Franc Zabkar
put finger to keyboard and composed:

It looks like U17 is a P-channel MOSFET. Normally in that position I
would expect it to be functioning as an external chopper for one of
the buck converters. However U16 has its own internal chopper. Is it
possible that U17 provides additional current for U16?

AF4407P, Anachip, P-Channel 30-V (D-S) MOSFET:
http://www.datasheetcatalog.org/data...7/270247_1.pdf

"Typical applications are PWM DC-DC converters, power management in
portable and battery-powered products ..."

AO4407, Alpha & Omega Semiconductor, 30V 12A P-Channel MOSFET:
http://aosmd.com/pdfs/datasheet/AO4407.pdf

"This device is ideal for load switch and battery protection
applications."

I wonder if U17 is a high-side power switch ???

- Franc Zabkar
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