Smart Module Series
SC200L_Series(Dual-band Wi-Fi)_Hardware_Design 35 / 111
1. It is recommended to switch off the power supply when the module is in abnormal state, and then
switch on the power to restart the module.
2. The module supports battery charging function by default. If the above power supply design is
adopted, please make sure the charging function is disabled by software, or connect VBAT to a
Schottky diode in series to avoid the reverse current to the power supply IC.
3.5. Turn On and Off the Module
3.5.1. Turn On the Module with PWRKEY
You can turn on the module by driving the PWRKEY pin low for at least 2.5 s. PWRKEY pin is pulled up to
VBAT internally. It is recommended to use an open drain/collector driver to control the PWRKEY pin. A
simple reference circuit is illustrated in the following figure.
Turn on pulse
PWRKEY
4.7 K
47 K
>2.5 s
R1
R2
Q1
R3
1K
Figure 6: Turn On the Module Using Driving Circuit
The other way to control the PWRKEY pin is by using a button directly. You must place a TVS component
nearby the button for ESD protection. A reference circuit is shown in the following figure.
PWRKEY
S1
Close to S1
TVS
1K
Figure 7: Turn On the Module Using Keystroke
NOTE