10 Bit SPI based Analog to digital converter Breakout

Pandi June 13, 2016 2 min read

MCP3008:

Tenet Technetronics introduces MCP3008 Breakout board in which, this device is a successive approximation 10-bit Analog to-Digital (A/D) converter with on-board sample and hold circuitry. The MCP3008 is programmable to provide four pseudo-differential input pairs or eight single-ended inputs. Differential Non linearity (DNL) and Integral Non linearity (INL) are specified at ±1 LSB. Communication with the devices is accomplished using a simple serial interface compatible with the SPI protocol. The device is capable of conversion rates of up to 200 ksps. The MCP3008 device operates over a broad voltage range (2.7V – 5.5V). Low-current design permits operation with typical standby currents of only 5 nA and typical active currents of 320 µA.

Teaching the Raspberry Pi how to read analog inputs is easier than you think! The Pi does not include a hardware analog-to-digital converter, but an external ADC (such as the MCP3008) can be used, along with some bit banged SPI code in Python to read external analog devices.

Here is a short list of some analog inputs that could be used with this Breakout board:

Potentiometer
photocell
force sensitive resistor (FSR)
temperature sensor
2-axis joystick and many more

Interfacing MCP3008 with 8 different sensors:

Here we are interfacing the MCP3008 breakout with 8 analog sensors with raspberry pi and we are making use of all 8 input channels of the the MCP3008 and shown the output in a serial window.