Neoway N720 - 2.6.2 ADC

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 26
Figure 2-19 Recommended level shifting circuit 2
220pF
TXD
5.6KΩ
47KΩ
4.7KΩ
VDDIO_IP8
2.2KΩ
220pF
47KΩ
10KΩ
Q1
Q2
MCU_URXD
VCC_IO
220pF
RXD
10KΩ
10KΩ
5.6KΩ
VDDIO_IP8
10KΩ
220pF
47KΩ
4.7KΩ
Q1
Q2
MCU_UTXD
VCC_IO
Components:
Q1/Q2: MMBT3904 or MMBT2222. High-speed transistors are better.
MCU_UTXD and MCU_URXD are respectively the TX and RX ports of the MCU, while UTXD and
URXD are respectively the TX and RX ports of the module.
Voltage at VCC_IO is the voltage at the UART of the MCU while voltage at VDDIO_1V8 is the voltage
at the UART of the module.
2.6.2 ADC
N720 provides two ADC channels, and the detectable voltage ranges from 0.1 V to 1.7 V. ADC pin
supports highest precision of 15 bit and it can be used for temperature and other check. If this pin is used
to measure SIM card temperature on power terminals, refer to Neoway GPRS Module ADC User Guide.