Usage Models - Sierra Wireless MC5725 Hardware Integration Manual

Rev 1.9.1 Feb.09
In the event of a discrepancy in values between this guide and the Product Specification Document (PSD), the PSD takes precedence.
The SED process is implemented as follows:
The modem tracks consecutive resets of the modem within
•
30 seconds of power‐on.
After a third consecutive reset occurs, the modem automati‐
•
cally waits up to 30 seconds in boot‐and‐hold mode,
waiting for a firmware download to resolve the power‐cycle
problem.
After 30 seconds (if no firmware download begins), the
•
modem continues to power‐on.
If the modem resets again within 30 seconds of power‐on,
•
the modem again waits in boot‐and‐hold mode.
This process continues until the unexpected power‐cycle issue
is resolved—either a firmware download occurs, or the
modem doesn't reset spontaneously within 30 seconds of
power‐on.

Usage models

Usage models can be used to calculate expected current
consumption. A sample usage model is provided in Table 2‐9,
based on the values in Table 2‐3 for a CDMA module.
Table 2-9: Power consumption of a sample application
Used by a field worker
(data only)
Upload (module 1000 kB/day
Tx)
Download 500 kB/day
(module Rx)
Coverage / data 1X / 80 kbps
rate
Hours of 8/day (off 16 hrs/day)
operation
Total power 60 mAh
consumed over
24 hours
This example model applies to a battery‐operated device. In
practice, because the module is isolated from the battery (the
host device manages the power source), the mAh ratings
depend on the device's supply efficiency.
The module automatically enters slotted sleep mode when
there is no transmission or reception occurring (SCI = 2).
Transmit power is assumed to be +3 dBm.
Proprietary and Confidential
Power Interface
Used for remote data
logging
40 kB/h
100 kB/day
IS-95 / 14.4 kbps
24/day
200 mAh
35