User's Manual

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4.
Power requirements
The RIM 902M radio modem must be provided with a clean power source
capable of delivering bursts of high current. This can be provided by a plug-in
power supply unit, a rechargeable battery pack, or single use batteries. RIM has
conducted extensive research and has developed guidelines for integrators to
follow when designing the power supply system for the RIM 902M.
Load specifications
The RIM 902M draws its power in bursts; the power required changes rapidly
depending on whether the radio is transmitting, receiving, or in standby. The
load profile is given on the following page. These specifications can be given
directly to your power supply designer or battery supplier.
Power supply parameters
The RIM 902M requires a clean, stable 4.15 to 4.75 volt source that is capable
of delivering a one-second burst of up to 1.7A when required by the transmitter.
Under non-ideal conditions such as an improperly matched antenna, however,
this burst could be as high as 2.2A. The receiver current consumption is 66 mA
and the standby current consumption is 0.07 to 0.2 mA. The maximum no-load