4-Channel 16-Bit ADC for Raspberry Pi (ADS1115)
The analog-to-digital converter(ADC) is a common accessory for Raspberry Pi. This is a 4-channel ADC based on Texas Instrument's ADS1115, which is a precision, low-power, 16-bit ADC chip. We make this ADC into a compact Raspberry Pi Zero form factor and integrated an analog Grove connector so that you can also use analog Grove modules with it.
- LOW current consumption:
- Continuous Mode: Only 150μA
- Single-Shot Mode: Auto Shut-Down
- Wide supply voltage range
- Input multiplexer (MUX) that provides two differential or four single-ended inputs.
- Programmable comparator
- Internal low-drift voltage reference
- Internal oscillator
- Internal PGA
- Programmable data rate: 8SPS to 860SPS
- I2C-compatible serial interface
|Supply Voltage||3.3V / 5V|
|Analog input current||100mA(momentary)
|Maximum junction temperature||150℃|
There are 4 possible I2C addresses of this grove, from 0x48 to 0x4B. The default I2C address is 0x48. You can change the I2C address by doing some soldering.
If SDA(corresponding address 0x4A) is used as the device address, hold the SDA line low for at least 100 ns after the SCL line goes low to make sure the device decodes the address correctly during I2C communication.
- Portable instrumentation
- Consumer goods
- Battery monitoring
- Temperature measurement
- Factory automation and process controls
|Arduino||Raspberry Pi||BeagleBone||Wio||LinkIt ONE|
|Raspberry pi||4-Channel 16-Bit ADC for Raspberry Pi(ADS1115)|
|Get ONE Now||Get ONE Now|
In this section, we will introduce you how to install the driver and how to enable I2C.
Enable I2C As I2C is not turned on by default, we need to configure I2C by hand.
- Step 1. Power up the Raspberry Pi.
- Step 2. Open raspi-config by typing following command in terminal.
- Step 3. Arrow down to 5 interfacing Options and press "enter" to select.
- Step 4. Arrow down to P5 I2C and press "enter" to select.
- Step 4. Select "Yes" to enable it.
- Step 5. Select "Ok".
- Step 6. Select "Finish" to save the changes.
Please follow the steps strictly when installing, otherwise the installation may failed or even damage the module.
- Step 1. Power up Raspberry Pi.
- Step 2. Open the terminal and type the following commands.
1 2 3
git clone https://github.com/Seeed-Studio/pi-hats.git cd pi-hats sudo ./install.sh -u adc_ads1115
- Step 3. Power off Raspberry Pi.
- Step 4. Insert the HAT to Raspberry Pi
- Step 5. Power up Raspberry Pi.
List install status
If your installation was successful, you should be able to see the following result.
1 2 3 4
pi@raspberrypi:~/pi-hats $ ./install.sh -l adc_ads1115 : installed rtc_ds1307 : not installed rtc_ds3231 : not installed
sudo ./install.sh -u
channels 0-3 is differntial voltage, full scale range -2.048V - +2.048V
channels 4-7 is absolute voltage of AIN0-AIN3, full scale range 0 - +2.048V
Read AIN0(channel 4) voltage(unit mV).
Read all channels the same time.
Take Grove - Sound Sensor as an example, if you use the grove cable to connect sound sensor with the ADC hat as shown below, it means you are using A0(channel four). Now, run the command ++./ads1115.s++ inside the terminal, you will be able to see the following result if it is reading data from the sound sensor.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
pi@raspberrypi:~/pi-hats $ ./ads1115.sh 3f804000.i2c four channels' value are : 1024 , 285 , 285 , 285 four channels' value are : 796 , 285 , 285 , 285 four channels' value are : 304 , 286 , 283 , 283 four channels' value are : 366 , 284 , 284 , 283 ^Cpi@raspberrypi:~/pi-hats $
You will be noticed that channel 5, 6, 7 is about fixed while channel 4 is reading some data.
[PDF] Datasheet ADS1115