MCP3008 I/O Expander¶
The Microchip Technology Inc. MCP3008 devices are successive approximation 10-bit Analogto-Digital (A/D) converters with on-board sample and hold circuitry.
Once configured, you can use any of the 8 pins as sensors for your projects.
Each pin will respond with a voltage calculated off of the reference_voltage (default is 3.3v). It calculates the voltage by multplying the reference_voltage * value on the pin (basically the percentage of VREF)
Most configurations will set the reference_voltage = VREF (pin 13 on the chip)
- If you want just the scaled value you can use the read_data function
float MCP3008::read_data(uint8_t pin)
# Example configuration entry mcp3008: cs_pin: D8 # Example config of sensors. # This is a NTCB3950 10K thermocoupler attached to pin 0 # of the MCP3008 with a 10K resistor as a voltage divider. # See `resistance` and `ntc` platorms for other options sensor: - platform: mcp3008 # Attached to pin 0 of the MCP3008. reference_voltage: 3.19 update_interval: 1s id: freezer_temp_source number: 0 # MCP3008 pin number - platform: resistance id: freezer_resistance_sensor sensor: freezer_temp_source configuration: DOWNSTREAM resistor: 10kOhm - platform: ntc id: freezer_temp sensor: freezer_resistance_sensor calibration: b_constant: 3950 reference_temperature: 25°C reference_resistance: 10kOhm name: Freezer Temperature
id (Required, ID): The id to use for this MCP3008 component.
cs_pin (Required, int): The SPI cable select pin to use