Service Guide

Table Of Contents
LTE Standard Module Series
EC200U_Series_Hardware_Design 33 / 94
DC_IN
MIC29302WU
IN OUT
EN
GND
ADJ
2 4
1
3
5
VBAT
100 nF
100 nF
100K
47K
470R
51K
1 %
1 %
4.7K
47K
VBAT_EN
470 μF
470 μF
Figure 9: Reference Circuit of Power Supply
3.6.4. Monitor the Power Supply
You can use AT+CBC to monitor the VBAT_BB voltage value. For more details, see document [2].
3.7. Turn on/Turn off/Reset
3.7.1. Turn on Module with PWRKEY
Table 10: Pin Description of PWRKEY
Pin Name
Pin No.
I/O
Description
Comment
PWRKEY
21
DI
Turn on/off the module
VBAT power domain
When the module is in power-off mode, it can be turned on to normal mode by driving PWRKEY to a low
level for at least 2 s. It is recommended to use an open drain/collector driver to control the PWRKEY. A
simple reference circuit is illustrated in the following figure.