The Adafruit AW9523 GPIO Expander and LED Driver Breakout adds 16 I/O pins to any I2C-capable microcontroller or single-board computer. What sets this expander apart is its built-in 256-step linear constant-current LED dimming — connect LEDs directly without current-limiting resistors for smooth, flicker-free dimming.

With STEMMA QT / Qwiic connectors for solderless I2C wiring, four selectable I2C addresses (up to 64 total I/O pins on one bus), and an interrupt output for pin-change notifications, this board is well suited for projects that need lots of controllable LEDs or additional GPIO.

Key Features

• 16× Multi-Function I/O Pins – Each pin configurable as GPIO input, GPIO output, or LED driver independently
• 256-Step LED Dimming – Linear constant-current drive eliminates the need for current-limiting resistors
• I2C Interface – Default address 0x58, selectable as 0x59, 0x5A, or 0x5B (up to 4 boards per bus)
• Interrupt Output – Pin-change IRQ with 8 µs deglitch, active low
• Open-Drain Support – First 8 pins configurable as open-drain outputs (as a group)
• 1.8V Logic Input – SDA, SCL, SHDN, and all GPIO accept 1.8V logic levels
• 2.5V to 5.5V Power Supply – Wide operating voltage range
• Shutdown Function – Low-level active supply shutdown for power management
• ESD Protection – ±4000V HBM
• STEMMA QT / Qwiic Connectors – Solderless I2C connection, chainable with other STEMMA QT devices
• Dimensions – 38.0 × 17.8 × 4.5 mm (1.5" × 0.7" × 0.2")

Ideal For

• LED matrix and indicator projects requiring smooth dimming
• Expanding GPIO on microcontrollers or Raspberry Pi
• Button/switch input expansion with interrupt notification
• I2C-controlled lighting installations

Package Contents

• 1× Adafruit AW9523 GPIO Expander and LED Driver Breakout