▲ 2 r/arduino
Hey guys,
I have a SIM808 module, an ESP32, and a 3.7V 2500mAh LiPo battery.
My wiring is:
TXD → GPIO16
RXD → GPIO17
VMCU → 3.3V
GND → GND
LiPo+ → SIM808 Battery +
LiPo- → SIM808 Battery -
With this setup, when I press POWKEY the LEDs turn on and I can successfully send AT commands and receive OK.
However, as soon as I insert the SIM card, the LEDs turn on briefly and then shut off immediately.
What could I be missing? Is this a power issue, capacitor issue, or something related to current draw when the SIM registers to the network?
u/TRASH_CAN_404 — 6 days ago