Pico 2 W Smart LED Matrix – Stellar Unicorn (16 x 16 – 256 pixels)

Our space Unicorns are very beautiful, all-in-one, RP2350-powered LED matrices perfect for conveying information fabulously (or for sprucing up your desktop, makingspace or Imaginarium). There are a ton of features aboard, here are some of our favourites!

• Loads of RGB LEDs, all with individual colour and brightness control. We’re in mad love with these big bright squircular LEDs with their rounded apertures and built-in diffusion.
• Looks great on video – invoking RP2350 magic means we can update the LEDs really quickly (we measured around 300 fps at 14-bit precision). This means there’s no nasty strobing, artifacting or brightness stepping when it’s filmed, so it’s perfect for adding to the background of your streaming setup.
• 2.4GHz wireless connectivity (courtesy of the Raspberry Pi Pico 2 W) so you can use it to display all sorts of interesting data from the internet.

There’s also an onboard amp and little speaker for bleepy alerts and *futuristic noises* and a battery connector so you can power it without it having to be tethered to a USB port. Every Unicorn comes with a pair of sleek little metal legs so it can stand up on its own (and has a selection of mounting holes if you’d prefer to do something else).

Use it to make a very fancy clock, a very fancy weather display or a very fancy output for sensors (other very fancy use cases are available).

We also have two other matrices with Pico 2 W in our store. Check out the Galactic and Cosmic Unicorn

Revision History

• As of 29th January 2025 – The older Stellar Unicorn has improved with Pico 2 W Aboard! Pico 2 W and its souped-up RP2350 chip brings some exciting improvements – including a higher core clock speed, double the on-chip SRAM and double the on-board flash memory. RP2350 adds hardware support for floating point number crunching, which means graphical effects and demos should run even faster!

Features

• Raspberry Pi Pico 2 W Aboard
• Dual Arm Cortex M33 running at up to 150MHz with 520KB of SRAM
• 4MB of QSPI flash supporting XiP
• Powered and programmable by USB micro-B
• 2.4GHz wireless
• 256 RGB LEDs in a 16×16 grid
• 3.5mm LEDs with rounded square apertures
• 6mm LED spacing
• Driven by FM6047 constant current LED drivers
• MAX98357 3.2W I2S Mono Amplifier (with 30mm 1W speaker)
• Phototransistor for light sensing
• 9 tactile user buttons
• Reset button
• 2x Qw/ST (Qwiic/STEMMA QT) connectors
• JST-PH connector for attaching a battery (5.5V max)
• Fully assembled
• No soldering required.

Getting Started

To make it easy to get started, all our Unicorns ship pre-loaded with pirate brand MicroPython and a demo reel of examples of pretty examples to stare at.

You can find more examples on Github:

• Unicorn MicroPython firmware and examples

Not your everyday RGB LEDs

In our software, we use the Pico 2 W’s PIOs (Programmable IOs) to drive the LEDs. Internally, Unicorn applies gamma correction to the supplied image data and updates the display with 14-bit precision resulting in extremely linear visual output – including at the low end.

The display is refreshed around 300 times per second (300fps!) allowing for rock-solid stability even when being filmed, no smearing or flickering even when in motion.

Resources

• Programmable with C/C++ or MicroPython
• Schematics
• Cut a Diffuser or 3D Print a Case
  • Stellar’s 4 mounting holes are M2 and 3mm in from the edge. The leg holes are M2.5.
  • .dxf files for the board outline 
    • With Corner Mounting Holes Only
    • With All Holes

Package Contents

• 1x Stellar Unicorn (with a speaker attached)
• 2 x Metal Legs
• 1x USB-A to Micro-B Cable

Notes

• Power consumption stats! We measured Galactic and Cosmic Unicorn as consuming just over 1A at maximum brightness, full white. When choosing a battery, consider that the LEDs will look their absolute best when they have access to at least 3.6V of power. At lower voltage levels you will start to see the blue elements of the LEDs fading out – this starts to become very noticeable at 2.9V and below. For best results when running on battery, we’d suggest using a chunky LiPo.
• Note that Unicorns have no battery charging hardware onboard –  this is so you can use either alkaline or LiPo batteries safely. You’ll need to charge up your LiPo battery with a separate battery charger (we like LiPo Amigo).
• Squircle alert! Some batches of Unicorns have LEDs with more rounded apertures (though the LED specs and brightness remain the same). They all look good, but if you want a perfectly visually matched pair (or stable) of Unicorns it’s probably best to buy them at the same time.