UMTS/HSPA Module Series
UG96 Hardware Design
UG96_Hardware_Design 29 / 76
3.6.4. Monitor the Power Supply
Command
AT+CBC
can be used to monitor the VBAT_BB voltage value displayed in millivolt. For more
details, please refer to
document [1]
.
3.7. Turn on and off Scenarios
3.7.1. Turn on Module Using the PWRKEY
The following table shows the pin definition of PWRKEY.
Table 7: Pin Definition of PWRKEY
Pin Name Pin No.
Description
DC Characteristics
Comment
PWRKEY
15
Turn on the module
V
IH
max=2.1V
V
IH
min=1.3V
V
IL
max=0.5V
Pull-up to VRTC
internally with 200K
Ω
resistor.
When UG96 is in power off mode, it can be turned on to normal mode by driving the PWRKEY pin to a low
level for at least 100ms. It is recommended to use an open drain/collector driver to control the PWRKEY.
After STATUS pin outputting a high level, PWRKEY pin can be released. A simple reference circuit is
illustrated in the following figure.
Turn on pulse
PWRKEY
4.7K
47K
≥
100ms
Figure 9: Turn on the Module Using Driving Circuit
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.