TechSense : Joy-Con build
15 Jan 2017I was planning on having something else this week, but none of them are in a state to be released, so it’s going to be another random tech related article instead.
The Nintendo Switch was announced this week and the cost of it’s controllers have caused quite a fuss. So I thought that I’d try to design my own version, based on the features they support and components I’ve used so I’ve got a reasonably good idea that it would work.
The parts
Here’s what I came up with, for the left Joy-Con. The right is pretty similar but with the IR camera in it.
| Part | Component | Price Each | Quantity | Price | Power/mAh |
|---|---|---|---|---|---|
| Switches | Right angle SMD | £0.23 | 7 | £1.61 | |
| Analog stick | ALPS RKJXU1210006 | £3.00 | 1 | £3.00 | |
| MCU | STM32F030C6T6 | £0.70 | 1 | £0.70 | 9.65 |
| Radio | Nordic Semiconductor nRF24L01P-R | £1.41 | 1 | £1.41 | 0.34 |
| Accelerometer | ST LIS2HH12TR | £0.39 | 1 | £0.39 | 0.18 |
| Gryoscope | ST L2G2ISTR | £1.10 | 1 | £1.10 | 2.82 |
| Crystal | 16MHz | £1.10 | 1 | £0.10 | |
| Battery | 580mAh NiMh cell | £2.41 | 1 | £2.41 | |
| Totals: | £11.72 | 35.49 |
This doesn’t include a voltage regulator, probably a boost converter due to the 1.2V battery, or the assembly, PCB, plastic parts, packaging and shipping but it’s getting there. I've based prices on buying everything in bulk (e.g. 1000 units) but I’m sure a full production run would be cheaper.
They haven’t really explained what the IR camera in the other Joy-Con can do (there was a brief mention that it can tell distance and guess hand shapes, like rock/paper/scissors), so I’ve no idea what part you’d need to use. I'm guessing it’s not Kinect like, as you can tell a hand moving towards or away by looking for a blob changing size and brightness, but I could be wrong.
I was wondering how you’d do the analog stick in suck a thin package, but came across the ALPS RKJXU1210006, which is designed exactly for this sort of device. They even do a slightly thinner one, but it’s not clear if it can do push to click.
The power usage estimate is based on sending an update every 14ms, about the same as Xbox One/PS4, and putting the parts into low power mode between. I've only done rough numbers, which work out around 6 hours of battery life, but doesn’t take into account losses from the voltage regulator and any savings by being more clever with sleep modes. If you knew the game wasn’t using the accelerometer/gryo you could stop sending updates if no buttons were being pushed and the analog stick was in the dead-zone, apart from a hello so it knew the controller was still connected. A lithium polymer battery with given them more capacity in the same space, a while it would raise the cost a little, would be worth it.
Conclusion
As with most console accessories I think Nintendo are going to be making a pretty good profit on them. In the UK a pack of both the left and right are £79, so assuming a 10% mark-up and VAT (20% in the UK) that’s £60 or £30 each (there’s probably import duty on them as well, but that’s far too complicated to even being to work out).
With the extra costs, and sourcing components cheaper, I wouldn’t be surprised if the total cost was around £15. Now we’ll just have to wait till the 27th of March when I’m sure iFixit will do a teardown showing us the insides :).