Key Features:
- It has 16 I/O pins, that'll double most boards' pin count
- Four I2C address options, so you can connect 4 expanders to one bus
- Each pin can be an input or an output
- IRQ output can alert you when input pins change value
- 8-bit linear constant-current LED dimming support so you can connect LEDs without resistors
Expand your project possibilities, with the Adafruit AW9523 GPIO Expander and LED Driver Breakout - a cute and powerful I2C expander with a lot of tricks up its sleeve.
GPIO expanders work like this: you have a board with some number of GPIO but not enough for your project - maybe you need more buttons or LEDs. You could upgrade to a board with massive number of GPIO like the Grand Central, or you could pop on one of these boards. Connect it over I2C and then you can send/receive I2C commands to control the GPIO pins to write and read them. It's going to be slower than direct GPIO access, but maybe that doesn't matter if it takes a millisecond instead of a microsecond. You only need the two I2C pins, and you can even share the I2C port with other sensors and devices. Heck, you can even add more expanders for massive I/O control!
Item Specifics
16 multi-function I/O, each for LED drive (current-source dimming) or GPIO mode
256 steps linear dimming in LED drive mode
Any GPIO can be configured as an input or an output independently
Support interrupt, 8us deglitch, low-level active
Standard I2C interface, AD1/AD0 select I2C device address
SDA, SCL, SHDN, and all GPIO can accept in 1.8V logic input
ESD protection: ±4000V HBM (MIL-STD-883H Method 3015.8 standard)
Latch-up :±450mA( JEDEC STANDARD NO.78C SEPTEMBER 2010 standard)
Supply shutdown function, low-level active
2.5V~5.5V power supply
I2C address default 0x58 (can be 0x59, 0x5A or 0x5B)
Dimensions: 38.0mm x 17.8mm x 4.5mm / 1.5" x 0.7" x 0.2"
Weight: 2.5g / 0.1oz