This guide was first published on Jul 11, 2014. It was last
updated on Jul 11, 2014.
This page (Pinouts) was last updated on Apr 24, 2019.
The TSL2591 is a I2C sensor. That means it uses the two I2C data/clock
wires available on most microcontrollers, and can share those pins with
other sensors as long as they don't have an address collision. For
future reference, the I2C address is 0x29 and you can't change it!
Vin - this is the power pin. Since the chip uses 3 VDC, we have
included a voltage regulator on board that will take 3-5VDC and safely
convert it down. To power the board, give it the same power as the logic
level of your microcontroller - e.g. for a 5V micro like Arduino, use
3vo - this is the 3.3V output from the voltage regulator, you can grab up to 100mA from this if you like
GND - common ground for power and logic
I2C Logic pins:
SCL - I2C clock pin, connect to your microcontrollers I2C clock line.
SDA - I2C data pin, connect to your microcontrollers I2C data line.
INT - this is the INTerrupt pin from the sensor. It can be programmed to do a couple different things by noodling with the i2c registers. For example trigger when a conversion is done, or when the light level has changed a lot, etc. We don't have library support for this pin