User's Guide

LE866 HARDWARE USER GUIDE 1vv0301210 Rev.0 Preliminary 2015-09-02 27 of 68
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Power on
The LE866 will automatically power on itself when VBATT & VBATT_PA are applied to the module.
VAUX / PWRMON pin will be at the high logic level and the module can be considered fully operating
after 5 seconds. The following flow chart shows the proper turn on procedure:
PWRMON=ON
?
“Modem ON Proc”
START
PWR Supply ON
PWRMON=ON
?
Delay = 300 ms
AT Init Sequence
Enter AT<CR>
N
Delay 1s 5s for Low Voltage
Operating
Y
Y
N
Y
Delay = 1 sec
N
Start AT CMD
AT Answer in
1sec?
Modem Reset Proc
N
Y