The SIM808_mini board uses a high-performance industrial-grade GSM/GPRS quad-band chip, and
integrates GPS and Bluetooth functions: SIM808, four frequency bands are available. Can realize
telephone voice, SMS (short message, MMS), GPRS data transmission function (support transparent
transmission mode, domain name resolution and IP mode), also has DTMF decoding (can identify the
other party's keys), GPS positioning, TTS voice function, upgraded version Also supports Bluetooth 3.0.
The hardware is upgraded on the basis of the hardware manual design, using low-ripple LDO power supply,
and the SIM card uses a gold-plated deck for better sensitivity.