Breakout Boards / Level Shifters & Expanders

You just found the perfect I2C sensor, and you want to wire up two or three or more of them to your Arduino when you realize "Uh oh, this chip has a fixed I2C address, and from what I know about I2C, you cannot have two devices with the same address on the same SDA/SCL pins!" Are you out of luck? You would be, if you didn't have this ultra-cool TCA9548A 1-to-8 I2C multiplexer ! Finally, a way to get up to 8 same-address I2C devices...

Because the Arduino (and Basic Stamp) are 5V devices, and most modern sensors, displays, flash cards and modes are 3.3V-only, many makers find that they need to perform level shifting/conversion to protect the 3.3V device from 5V. We do have some other handy level shifters in the shop, from the DIP 74LVC245 to the fancy bi-directional TXB0108. However, neither of these are happy to work with I2C, which uses a funky pull-up system to transfer...

Because the Arduino (and Basic Stamp) are 5V devices, and most modern sensors, displays, flash cards and modes are 3.3V-only, many makers find that they need to perform level shifting/conversion to protect the 3.3V device from 5V. Although one can use resistors to make a divider, for high speed transfers, the resistors can add a lot of slew and cause havoc that is tough to debug. For that reason, we like using 4050/74LVC245 series and similar...

Level shifting chips let you connect 3V and 5V devices together safely. This chip is similar to others in the shop (such as the 74LVC125) except this one is particularly good at converting 3V logic up to 5V . This is in demand especially when connecting some 3V devices such as the Teensy 3 to NeoPixels! Just power the 74AHCT125 with 5V, it will detect 3V logic properly. You can also use it to connect 5V logic out to 3V logic in, that's when...

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...

As we've been adding  STEMMA QT connectors to our breakouts and dev boards, folks have been really enjoying the simplicity and speed of plugging in I2C sensors and devices for quick iteration and design. That's all good, but I2C wasn't really designed for hot-plugging. You're kinda supposed to have everything connected once on boot and never mess with it - I2C was specified for on-board connections. And, folks who have...

Because the Arduino (and Basic Stamp) are 5V devices, and most modern sensors, displays, flash cards and modes are 3.3V-only, many makers find that they need to perform level shifting/conversion to protect the 3.3V device from 5V. Although one can use resistors to make a divider, for high speed transfers, the resistors can add a lot of slew and cause havoc that is tough to debug. For that reason, we like using 4050/74LVX245 series and similar...

Run two solenoids, or a single DC motor with up to 800mA per channel using the super-simple L9110H H-bridge driver. This bridge chip is an 8 DIP package so it's easy to fit onto any breadboard or perfboard. Each chip contains one full H-bridges (two half H-bridges). That means you can drive 2 solenoids or a single DC motors bi-directionally. Just make sure they're good for under 800 mA since that's the limit of this chip. They do...

Sometimes you'll find yourself with an I2C bus controller on one side, and an I2C bus device on the other and you gotta keep em (electrically) separated. Maybe because one is Earth-grounded, maybe because you've got some funky power monitoring setup, maybe you want to reduce noise. Whatever it is, you can use the  Adafruit ISO1540 Bidirectional I2C Isolator to add full electrical isolation between two sides of an I2C bus. The chip...

Do you have too many sensors with the same I2C address? Put them on the SparkFun Qwiic Mux Breakout to get them all talking on the same bus! The Qwiic Mux Breakout enables communication with multiple I2C devices that have the same address that makes it simple to interface with. The Qwiic Mux also has eight configurable addresses of its own, allowing for up to 64 I2C buses on a connection. To make it even easier to use this multiplexer, all...

Sometimes you feel low, and sometimes you feel high - cause your logic levels are opposite what they should be! But this easy-to-use inverter chip will flip that frown upside-down. This chip is spec'd to run at 5V but we've run it at 3V just fine. Power it by connecting up GND and VCC to your desired output logic level. High-level inputs can be as low as 2V and the output will be inverted on each of the 6 pairs of inverters. It's...

The Raspberry Pi is an amazing single board computer - and one of the best parts is that GPIO connector! 40 pins of digital goodness you can twiddle to control LEDs, sensors, buttons, radios, displays - just about any device you can imagine. This Adafruit GPIO Expander Bonnet will give you even more digital deliciousness - 16 more digital input/output pins are yours for any desire you have. The outputs are grouped into two 16-pin connectors that...

Since we first started carrying NeoPixels back in 2012, the chainable RGB LEDs have taken over the world. And a big part of that success is due to the simplicity of their wiring - just one data wire, no matter how many pixels you've got. So no surprise they're everywhere , blinking away in art exhibits, maker faire demos, DJ booths, decorations and costumes. But, at some point, every NeoPixel'er bumps into the constraints of that...

Most of our customers love using the Arduino for prototyping, design and invention but find themselves stuck when trying to connect the Arduino to the latest sensors, displays, controllers, interfaces, etc. as they are almost all 3.3V logic these days. We try to solve this problem by having all our breakout boards be 5V compatible or when that's not possible, including a level shifter chip but there are still thousands of tempting devices...