Raspberry Pi 400: Its designer reveals more about the faster Pi 4 in the $70 PC's keyboard

Raspberry Pi designer shows off the custom PCB for the Raspberry Pi 4 inside the new $70 Pi 400 keyboard computer.

Lockdown surge for Raspberry Pi sales

Raspberry Pi's designers have revealed more about the overhauled design of the Raspberry Pi 4 inside its new Raspberry Pi 400 keyboard computer.   

The new $70 Raspberry Pi 400, announced on Monday, offers fans of the Raspberry Pi single-board computer a polished, modern take on far less powerful classics from the 1980s like the BBC Micro, ZX Spectrum and Commodore Amiga.          

While the squarish Raspberry Pi 4 measures 85.6mm × 56.5mm, or 2.22 inches × 3.37 inches, the designers of the Pi 400 crafted an elongated custom printed-circuit board (PCB) to fit the Pi 400 computer keyboard's dimensions of 286mm × 122mm × 23mm, or 11.25 inches × 4.8 inches × 0.9 inches. 

SEE: Hiring Kit: Python developer (TechRepublic Premium)

The Pi 400 shares the Pi 4's circuit layout for power management, processor, and memory. However, the designers had to reposition the GPIO connector and ports to suit the keyboard's ports, which are all located on the rear of the computer. Also, the keyboard has a dedicated USB2.0 port.  

Raspberry Pi senior principal engineer Simon Martin has posted a blog answering the questions some fans have raised about whether the Pi 400 is a left-handed device. 

The USB ports are located on the left side of the keyboard's rear, which can make a cable-connected mouse a tangly experience for right-handed users. He concedes it was a right-handed design challenge that he couldn't solve but notes it isn't a problem for right-handed users with a Bluetooth mouse. 

"The PCB shape had to be defined early on so that the industrial designers could get on with the housing design, and I then stared endlessly at the PCB layout, trying to get one of the USB ports to route to the right side without wrecking the signal integrity of the memory or the HDMI; I could not find a way to do this," writes Martin. 

While Raspberry Pi single-board computers don't come with a heatsink, the Pi 400 includes one to offset its higher 1.8GHz operating point – the Raspberry Pi 4 runs at 1.5GHz. 

"Raspberry Pi 400 contains a heat spreader that dissipates the heat across the whole unit, front and back, so that no part of it will feel too hot to touch. In fact, there is enough thermal margin to overclock it, if you're so inclined," Martin notes. 

SEE: Raspberry Pi 400 is out: $70 for a complete PC with a faster Pi 4 in a keyboard

Martin explains that the Pi 400 team didn't opt for the Raspberry Pi Compute Module – a compact variant of the board without ports for industrial applications – because it was more efficient to make a custom PCB at the scale at which the Pi 400 is being made at Sony's manufacturing facility in Wales

"With hundreds of thousands of Raspberry Pi 400 units in the first instance, we are above that scale," boasts Martin. 

Finally, the Pi 400 marks the first Raspberry Pi product with an on/off power button, albeit a two-key affair that works by pressing Fn+F10. Pressing the pair for two seconds restores power.   

rpi400-innards-1536x1097.jpg

The Pi 400's designers opted to create an elongated custom printed-circuit board to fit the computer's keyboard.

The Raspberry Pi Foundation

More on Raspberry Pi and single-board computers

  • Raspberry Pi 400 is out: $70 for a complete PC with a faster Pi 4 in a keyboard    
  • Raspberry Pi 4: Higher-quality, faster graphics edge closer with Vulkan support via Mesa  
  • Raspberry Pi Compute Module 4 is out: $25 with a new form factor and new connectors  
  • Google's $100 Linux Coral Dev Board mini quietly launches – but sells out fast  
  • Windows 10 Raspberry Pi rival: Intel Atom chip powers this new Rock Pi X board  
  • Raspberry Pi: Banana Pi maker touts this new rival board with Amlogic chip and 4GB RAM  
  • Raspberry Pi 4 faces $59 Rock Pi 4C challenger with dual display output  
  • Raspberry Pi: Now computer-vision apps get boost with Khronos OpenVX API  
  • New Raspberry Pi OS update: First 8GB Pi 4, now you get these latest features  
  • New Raspberry Pi 4: 8GB RAM model out now for $75 – plus you get a new 64-bit OS  
  • New Raspberry Pi 4 update beta lets you boot from a USB mass storage device  
  • Raspberry Pi reveals this new $50 high-quality Pi camera with interchangeable lenses  
  • Raspberry Pi alternative: New Odroid-C4 undercuts 4GB Raspberry Pi 4 by $5  
  • Raspberry Pi sales jump: Here's why the tiny computer's in demand in coronavirus crisis  
  • Raspberry Pi 4's big price cut: 2GB model gets massive birthday reduction  
  • Raspberry Pi's Raspbian gets new features: File manager, Thonny Python IDE updates  
  • Raspberry Pi 4 graphics win: Open-source Vulkan driver support is coming  
  • Raspberry Pi gets MIT's Scratch 3 programming language for Raspbian  
  • Raspberry Pi 4 and Raspbian Buster: Hands-On   
  • Raspberry Pi 4 won't work with some power cables due to its USB-C design flaw
  • Raspberry Pi 4 Model B is out: Faster CPU, GPU, dual-screen 4K, up to 4GB for $55
  • Raspberry Pi users: You got Pi 4, now new Raspbian takes Windows 10, iOS design cues
  • What are the best Raspberry Pi alternatives? Everything you need to know about Pi rivals
  • What is the Raspberry Pi 4 Model B? A closer look at the new board and what it can do TechRepublic
  • Raspberry Pi 4 Model B review: This board really can replace your PC TechRepublic
  • Raspberry Pi 4 : This thing is a PC, says board's creator Eben Upton TechRepublic
  • New Raspberry Pi add-on: Now you can monitor air pollution indoors and out
  • Raspberry Pi: A cheat sheet TechRepublic  
  • Google includes a Raspberry Pi in a DIY smart speaker kit CNET