User's Manual

GE866-DUAL Hardware User Guide
1VV0301051 Rev. 2 – 2014-04-07 7
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Mod. 0805 2011-07 Rev.2
The three cells Ni/Cd or Ni/MH 3.6 V Nom. battery types or 4V
PB types MUST NOT BE USED DIRECTLY since their maximum voltage
can rise over the absolute maximum voltage for the GE866-QUAD
and damage it.
NOTE:
DON'T USE any Ni-Cd, Ni-MH, and Pb battery types directly
connected with GE866-QUAD. Their use can lead to overvoltage
on the GE866-QUAD and damage it. USE ONLY Li-Ion battery types.
• A Bypass low ESR capacitor of adequate capacity must be
provided in order to cut the current absorption peaks, a
100µF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor (usually a tantalum one) is
rated at least 10V.
• A protection diode should be inserted close to the power
input, in order to save the GE866-QUAD from power polarity
inversion. Otherwise the battery connector should be done
in a way to avoid polarity inversions when connecting the
battery.
• The battery capacity must be at least 500mAh in order to
withstand the current peaks of 2A; the suggested capacity
is from 500mAh to 1000mAh.
6.3.2. Thermal Design Guidelines
The thermal design for the power supply heat sink should be
done with the following specifications:
See Par. 6.2 Power Consumption
NOTE:
The average consumption during transmissions depends on the
power level at which the device is requested to transmit by
the network. The average current consumption hence varies
significantly.
Considering the very low current during idle, especially if
Power Saving function is enabled, it is possible to consider
from the thermal point of view that the device absorbs current
significantly only during calls.