Real World (Unexpected) Examples of a Multi-Board PCB System
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What do reusable rockets, self-driving cars, and the blockchain have in common? Besides breaching major milestones in the last 3-5 years, they are all stellar examples of how advancements in multi-board printed circuit board (PCB) design is propelling us into the future. In this post we’ll look at how advances in multi-board PCB systems are helping push the boundaries of spaceflight, autonomous vehicles, and the blockchain.
Redefining the Costs of Spaceflight
Ever wonder what it takes to repeatedly land a rocket on an autonomous barge in the middle of the Atlantic, at a fraction of the cost of a conventional launch?
On-board avionics must manage foldable heat-resistant wings called grid fins to steer the first-stage reentry into Earth’s atmosphere. Cold-gas thrusters must flip the rocket 180° and align it for landing. Lightweight carbon fiber landing legs deploy just in time for touchdown.
It’s even more impressive when you consider that all of the supporting electronics and control systems must survive the heavy g-forces, radiation, and temperature swings experienced during launch and re-entry.
In addition to the obvious cost savings of being able to reuse a rocket, build costs are further reduced thanks to SpaceX’s policy of vertical integration on the manufacturing floor—they try to make as many of the components of a Falcon 9 in-house as possible.
The wide availability of multi-layer boards, high performance CPUs, integrated circuits, premade modules, and other components makes building custom in-house electronics a viable option. Furthermore, advancements in PCB design software made it practical to design the complex avionics systems that make a self-landing rocket possible.
Self-Driving Cars
Anyone who has ever battled rush hour traffic on their daily commute to work, can testify that humans are pretty terrible drivers. Wouldn’t it be great if you could kick back and catch up on sleep, work, Netflix, or literally anything else while your car drove you to your destination?
It’s one of the many reasons that Waymo, General Motors, Daimler, Ford, and a host of other auto companies are racing to create self-driving vehicles. The technical challenge is also something any PCB designer can appreciate.
Vehicles have already been getting smarter, long before the first self-driving prototypes arrived on the scene. From the radio on your dash to rear-view cameras, smarter fuel injectors, and driver assist, your modern automobile is already an impressive example of a multi-board PCB system.
Self-driving cars take this to the next level, with smart sensors, advanced Lidar, and camera arrays streaming huge volumes of real-time data to a powerful on-board computer. Even chipmakers such as Qualcomm, Nvidia, and Samsung are lining up to help supply automakers with the “brains” needed to operate a self-driving car.
Automakers use conventional multi-layer PCBs for many of the mechanical and electrical systems that help a vehicle drive itself. As with SpaceX’s self landing rockets, the challenge is picking the right off-the-shelf components and interconnects for the job. From heat waves to blizzards, cars must endure a wide range of conditions, both on and off the road.
Cryptocurrency Mining and the Blockchain
You may have noticed the sharp rise in the price of GPUs, particularly high-end gaming cards towards the end of 2017. You may also remember when cryptocurrency mania reached a fever pitch in December of 2017 when the price of a single bitcoin peaked just shy of $20,000. And after the crash in the price of Bitcoin earlier this year, the prices of GPUs have finally begun to return to normal.
This was not a coincidence. The story of blockchain and cryptocurrency mining is very much one of multi-board PCB design. And chip manufacturers are aware of this link. There’s a reason Asus just revealed their B250 Mining Expert motherboard which supports up to 19 GPUs. It sports 18 PCIe 3.0 x1 slots and a physical 3.0 x16 slot.
To understand the connection, one must understand the blockchain and how cryptocurrencies work. With paper money, monetary policy from established banks and governments decide how money is printed and distributed. The value of a conventional currency is backed by these institutions.
With cryptocurrencies, it’s a bit more technical. Cryptocurrency is validated by a distributed ledger system called the blockchain, which uses a combination of digital signatures and cryptographic hash functions to provide both transparency and security.
Each block is like a page in a physical ledger. Transactions are recorded until a block is full. Once completed said block gets appended to the larger blockchain which contains a record of every previous transaction.
Now here’s the important part. Cryptocurrency mining is the only way to add new coins to the system. By design, it takes a lot of computational work to process the hash functions that add a valid block to the blockchain. As a reward for performing this computational work, the person or organization maintaining a copy of the blockchain has the chance to be awarded a coin. This gets more difficult the longer the chain gets, creating a digital arms race among fellow miners.
And what’s the best way to increase the computational power of your mining rig? Well since everyone is restricted to the same software, it really boils down to adding more GPUs. How’s that for a multi-board PCB system?
Multi-Board PCB Design Is Reshaping Our World
From cheaper space travel to self-driving cars and digital currencies—advances in PCB technology are the hidden force behind many of today’s technological innovations. Feeling inspired to launch your own multi-board PCB project? Check out Cadence’s suite of PCB design and analysis tools today.