User's Guide

LE940B6 HW User Guide
Rev. 2.02
Page 49 of 111 2020-01-10
Figure 5 shows a flow chart for the proper power-up procedure:
Figure 5: Power-up Flow Chart
Modem ON Procedure
START
VBATT > 3.4V ?
VAUX/PWRMON = ON?
ON_OFF_N = LOW
80 ms < Hold Time < 120 ms
ON_OFF_N = HIGH
VAUX/PWRMON = ON?
Delay = 25 sec
Go to
Start AT CMD
Modem ON Procedure
END
N
Y
Y
N
Go to
HW SHUTDOWN
Unconditional
N
Y
Provided to Dekra under NDA
Distribution is Prohibited except for
Dekra employees with a Need to know