User's Manual

Smart Machine Smart Decision
SIM7020G_User Manual_V1.00 31 2019-01-15
it is strongly recommended to follow these guidelines while designing:
⚫ Make sure that SIM card holder should far away from NB_IOT antenna while in PCB
layout.
⚫ SIM traces should keep away from RF lines, VBAT and high-speed signal lines.
⚫ The traces should be as short as possible.
⚫ Keep SIM holder’s GND connect to main ground directly.
⚫ Shielding the SIM card signal by ground well.
⚫ Recommended to place a 100nF capacitor on SIM_VDD line and keep close to the holder.
⚫ Add some TVS and the parasitic capacitance should not exceed 50pF, and 22Ω resistor in
serials the SIM signal could enhance ESD protection.
3.8 Network status
The NETLIGHT pin is used to control Network Status LED, its reference circuit is shown in the
following figure.
Module
NETLIGHT
VBAT
4.7K
47K
R
Figure 20: NETLIGHT reference circuit
Note: The value of the resistor named “R” depends on the LED characteristic.
Table 16: NETLIGHT pin status
NETLIGHT pin status
Module status
64ms ON, 800ms OFF
No registered network
64ms ON, 3000ms OFF
Registered network
64ms ON, 300ms OFF
Data transmit
OFF
Power off or PSM mode
Note: NETLIGHT output low level as “OFF”, and high level as “ON”.