NB-IoT Module Series
BC66 Hardware Design
BC66_Hardware_Design 22 / 50
Another way to control the PWRKEY is using a button directly. When pressing the key, electrostatic strike
may generate from the finger. Therefore, a TVS component is indispensable to be placed nearby the
button for ESD protection. A reference circuit is shown in the following figure.
PWRKEY
S1
Close to S1
TVS
Figure 6: Turn on the Module Using Keystroke
The turn on scenario is illustrated in the following figure.
PWRKEY
VDD_EXT
41.25ms
TBD
VBAT
Module
Status
OFF
RUNNING
BOOTING
Figure 7: Turn-on Timing
3.7.2. Turn off
The module can be turned off by switching off the VBAT power supply.