AL3A-RM User Guide Version B
Document Number: 451-93156-002B
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the A3LA-RM during a call is an indication that the DC power source is unable to sustain voltage
above 4.0 V at peak current demand.
power profile of the A3LA-RM.
The A3LA-RM accepts 4.0 V to +5.4 V or +5.0 V to +32 V input. The A3LA-RM is shipped
with hardware set for +5.0 V to +32 V input. It can be changed to +4.0 V to +5.4 V input through
an internal jumper—POWER MUST BE DISCONNECTED BEFORE RESETTING THE JUMPER. Find
the jumper by removing the modem’s bottom plate. With the A3LA-RM held in the position
(DB25 connector to the left), the A3LA-RM is set for 4.0 V to +5.4 V when the
red jumper is on the middle and left pins, and it is set for +5.0 V to +32 V when the jumper is on
the middle and right pins. Each pin is also labeled with 5 V and 32 V to the left and right pins,
respectively.
Note:
Remember the input voltage setting on the A3LA-RM and do not apply voltage above the
maximum limit (of either 5.4 V or 3 2V). The A3LA-RM will be damaged beyond repair with
warranty voided if this were to occur.
Figure 2: Power Input Setting for the A3LA-RM
Important:
You can remove the A3LA-RM’s bottom plate to set the jumper but not for repair or
services. The warranty is voided if the A3LA-RM is disassembled for any reason other than to
set the jumper.
2.4
P
OWER
O
N
/O
FF
C
ONTROL
With the EXT_ON_OFF pin left unconnected, the A3LA-RM automatically turns on or off when
external DC power is applied or removed. Prior to turning the A3LA-RM off, issue command
AT*P0
to ensure all memory write activity is completed. When the A3LA-RM is powered off, its
Red jumper used to
set input voltage
range
