# Adafruit AW9523 GPIO Expander and LED Driver Breakout - STEMMA QT / Qwiic

**Type:** Product page · **SKU:** ADA4886 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/adafruit-aw9523-gpio-expander-and-led-driver-breakout-stemma-qt-qwiic.html ([markdown](https://core-electronics.com.au/adafruit-aw9523-gpio-expander-and-led-driver-breakout-stemma-qt-qwiic.html.md))

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 it's sleeve.

## Pricing

- **Price:** $9.70 (inc GST) — $8.82 AUD, exc GST
- **Quantity discounts:** 10+ $8.55 (exc GST) · 50+ $8.38 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 2 today, and up to 500 more in 7–12 days.

## Description

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 it's 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](https://core-electronics.com.au/search?q=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!

The AW9523 is a twist on the common I2C expander:

- First up, its very affordable - who doesn't love that?
- 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
- This chip *does not* support internal pull-ups or pull-downs, you will need to add an external resistor if you need one
- However, it *does* have 8-bit linear constant-current LED dimming support so you can connect LEDs without resistors and have great looking dimming without PWM
- The first 8 pins can be configured as open drain (as a group)

The lack of internally-configurable pull's is a bit of a bummer, but we think the expander more than makes up for it with the constant-current LED drive. If you're using an expander to add lots of controllable LEDs, this board will make it very easy. Since its constant-current, you *don't* need resistors in line with each LED (although it won't hurt if you do): simply connect the LED anode to one of the many VIN pads, then connect the cathode to the GPIO pin.

Of course, you can control any buttons or other I/O with the pins - Adafruit just think this board is particularly suited to LED driving. There's also an interrupt output, you can enable the pin-change IRQ for any pins so you can be notified when its time to read the I/O states.

One oddity about this chip is the default I2C address determines the initial boot-state of the pins. Adafruit's libraries immediately soft-reset and configure all the pins to inputs and push-pull so you can expect the same behavior no matter what the I2C address is. However, Adafruit recommend you check the datasheet Table 1 to make sure this doesn't affect your hardware.

Arduino have[ written both Arduino](https://github.com/adafruit/Adafruit_AW9523) and [CircuitPython/Python libraries](https://github.com/adafruit/Adafruit_CircuitPython_AW9523) for the AW9523, so you can get started whether you have an Arduino-compatible UNO or a Raspberry Pi 4 - or anything in between.

To get you going fast, Adafruit spun up a custom made PCB in the[ **STEMMA QT** form factor](https://core-electronics.com.au/search?q=stemma%20qt%20sensor), making it easy to interface with. The [STEMMA QT connectors](https://learn.adafruit.com/introducing-adafruit-stemma-qt/what-is-stemma-qt) on either side are compatible with the [SparkFun Qwiic](https://core-electronics.com.au/catalogsearch/result/?q=qwiic) I2C connectors. This allows you to make solderless connections between your development board and the AW9523 or to chain it with a wide range of other sensors and accessories using a [**compatible cable**. **QT Cable is not included**, but Adafruit have a variety in the shop](https://core-electronics.com.au/search/?q=stemma+qt+cable).

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/4/8/4886-00.jpg)