Product Info

LTE Standard Module Series
EC21_Series_Mini_PCIe_Hardware_Design
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Table 14: Airplane Mode Controlled by Software Method
3.10.4. PERST#
The PERST# signal can be used to force a hardware reset on the card. The module can be reset by
driving the PERST# signal low for 150–460 ms and then releasing it. The PERST# signal is sensitive to
interference. The traces should be as short as possible and be surrounded with ground.
The reset scenario is illustrated in the following figure.
V
IL
≤ 0.5 V
V
IH
≥ 2.3 V
VCC_3V3
≥ 150 ms
Resetting
Module
Status
Running
PERST#
Restart
≤ 460 ms
Figure 12: Reset Timing
3.10.5. LED_WWAN#
LED_WWAN# is an open collector output signal, it is used to indicate the network status of the module,
and maximum input current can up to 40 mA. According to the following circuit, in order to reduce the
current of the LED, a resistor must be placed in series with the LED. The resistance value can be
adjusted according to the brightness of the LED light.
The LED is emitting light when the LED_WWAN# output signal is active LOW.
AT+CFUN=? RF Function Status Module Operation Mode
0 RF and (U)SIM card disabled Minimum functionality mode
1 RF enabled Normal mode
4 RF disabled Airplane mode