Intermec Intellitag IM4, Руководство интегратора

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How the IM4 Operates
14 IM4 Module Integration Guide
How the IM4 Operates
Overtemperature Mode Standard Mode
IM4 is in Sleep mode
Did
the IM4 receive
a request for a tag
operation from an
application?
Is the IM4
temperature within
normal limits?
The IM4's ability to return to
normal status depends on the
ability of the card to dissipate
the heat.
The IM4 is designed to operate
at 1 Watt of continuous power
between -20
˚
C and 55
˚
C (-4
˚
F to
131
˚
F). These limits are not user
programmable.
IM4 API returns "Status=Normal"
and data, if found.
Application checks reason
for failed status and returns
overtemperature condition.
IM4 API returns
"Status=Failed."
Yes
No
Yes
No
This flow chart illustrates how the IM4 operates in Overtemperature mode and in Standard mode.
Heat Dissipation Requirements
In most usage scenarios, the IM4 uses a maximum of 4.5 W of power from
its host device. Since its RF transmit power is 1 W, it needs to dissipate up
to 3.5 W of heat. Normally, the host naturally dissipates this heat.
However, under high ambient temperature conditions or in a high duty
cycle application, this heat may need to be conducted outside the host to
prevent the IM4 from entering Overtemperature mode. The IM4 has a
built-in Overtemperature mode that will sufficiently protect it against very
high temperatures. When it enters Overtemperature mode, it shuts down
until it is cool enough to continue operating.