User's Guide

LE910Cx HW User Guide
Doc#: 1VV0301298
Rev. 13.0 Page 42 of 124 2019-07-15
5. Hardware Commands
Turning on the LE910Cx Module
To turn on the LE910Cx module, the ON_OFF_N pad must be asserted low for at least 1
second and then released.
The maximum current that can be drained from the ON/OFF # pad is 0.1 mA. This pin is
internally pulled up; customers should expect to see ~ 800 mV on the output.
Figure 4 illustrates a simple circuit to power on the module using an inverted buffer output.
Figure 4: Power-on Circuit
NOTE:
Recommended values R2 = 47 kΩ, R1 = 10 kΩ.
Initialization and Activation State
After turning on the LE910Cx module, a predefined internal boot sequence performs the
HW and SW initialization of the module, which takes some time to complete fully. During
this process, the LE910Cx is not accessible.
As shown in Figure 5, the LE910Cx becomes operational at least 20 seconds after the
assertion of ON_OFF.
NOTE:
During the Initialization state, AT commands are not available. The DTE host
must wait for the Activation state prior to communicating with the LE910Cx.