LG KP500 - Charging Circuit

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3. TECHNICAL BRIEF
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3.13 Charging circuit
ISL9221 accepts two power inputs, normally one from a USB (Universal Serial Bus) port and the other
from a desktop cradle.
The ISL9221 features 28V and 7V maximum voltages for the cradle and the USB inputs respectively.
Due to the 28V rating for the cradle input, low-cost, large output tolerance adapters can be used
safely.
Figure 19 Charging circuit
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