Monk Makes Sensor Board for MICRO:BIT

• Sensor Board with a LED ‘power on’ indicator
• Detects sound level with a MEMs (microphone on a chip) and a pre-amplifier
• Uses a thermistor to measure temperature
• Light level detection with a phototransistor (0 to 1023)
• 3V and GND connections can power a second board such as the Monk Makes Relay for MICRO:BIT or the Monk Makes Speaker for MICRO:BIT
• Compatible with the BBC micro:bit Programmable Board(not included)

The Monk Makes Sensor Board for MICRO:BIT allows you to sense sound level, temperature and light level. The Sensor for micro:bit uses a MEMs (microphone on a chip) and a pre-amplifier. The output of the sound sensor is connected to an analog input where it can be sampled. The sound signal varies about the 1.5V level. So, silence will produce an analog output of around 1.5V.

It uses a thermistor to measure temperature. The temperature output from the board is a voltage that indicates the temperature. This is then measured using an analog input on the micro:bit. If you want your temperatures in Fahrenheit, then multiply the temperature in degrees C by 9, divide the result by 5 and then add 32.

The light sensor uses a phototransistor to measure the light level and produces an output voltage that increases as the light level increases. Here is a guide to the kind of light level you might get from the sensor under different conditions (0 to 1023).

• Dark 0 to 3 
• Dimly lit room 6 to 10 
• Indoors directly under a light 10 to 50 
• Outdoors (dull day) 100 to 200 
• Outdoors (sunny day) 800 to 900 

Even though the maximum analog read value is 1023, the maximum reading from this sensor is around 900.