Power On/Off Control; Typical Power Usage Profile - Iridium 9603 Developer's Manual

Iridium 9603 SBD Transceiver Product Developers Guide
Revision 3.1
3.2.1

Power On/Off Control

An external on/off input is provided on a pin of the User connector. The 9603/9603N starts up when power is applied and the
power on/off input is high. As long as the input voltage is applied, logic high on this line turns the transceiver on and a logic low
turns it off. If this line is not required then it must be connected directly to the +5 V supply.
Note that this on/off control is similar to the Iridium 9601 and 9602 products, but it is not the same as the 9522, 9522A or 9522B
products.
Prior to turning off the modem a "flush memory" (AT*F) command should be issued to ensure all memory write activity is
completed. When a transceiver has been turned off, Product Developers should not reapply power on a unit until more than 2
seconds has elapsed after power has reached 0V. Additionally, if a unit does not respond to AT commands, power off the module,
wait for 2 seconds and then power it back on.
When a 9603/9603N is powered off the power on reset circuit requires 2 seconds for voltages to decay. If the 2 second wait time is
not adhered to the reset circuit may not operate and the modem could be placed in a non-operational state. The state is not
permanent and can be rectified by the above procedure.
3.2.2

Typical Power Usage Profile

This section is designed to give the Product Developer some insight to the electrical power profile that the 9603/9603N uses. It
does not describe every situation and permutation possible. It should be used as a starting point for the Product Developer to
continue its own development design. The actual usage profile can vary for a number of reasons:
View of the sky – if in poor visibility of the sky where a clear line of sight is not available between the transceiver and the
1)
satellite.
2) The higher the antenna VSWR the higher the current consumed
3) How often the 9603/9603N module is activated/deactivated by the Host Controller system
4) Manufacturing variation from transceiver to transceiver.
The host system designer should ensure their design covers for worst case power consumption scenarios.
Proprietary & Confidential Information
Distribution of guide restricted to product developers only • Information contained in this guide is subject to change without notice.
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