OpenSource Hardware is a trend in recently life or we could say, it is old fashion way. I am glad to find it makes the world better.
But NOW I must talk on a serious topic: Why NOT Open Source Hardware?
Somebody may ask, is VoCore an open source hardware?
Not at all, please give me five minutes to explain.
How to define an open source hardware?
First, let’s check open source software:
They are totally free to use, everybody could modify it, contribute to it, once you have the source code, it is totally under your control.
You might say, I cloned the Arduino from scratch, even from a hand-making PCB, and everything just works well;
Ye, you are right, you made one open source hardware. But I have to say, Arduino is very simple that is why you can make it.
Here is a true story.
A student from India contact me, he want to make some copys to lower the cost, I think it is a good start of the open source hardware, so I spend a lot of time and tried my best to help him but fail at final…After a lot of work, he finally make some copy, but its cost is 3 times than current VoCore2… Of course for fun it worth. 🙂 And I recognize VoCore2 should not be open source:
1. PCB quality is important, for example, at solder layer it even covers the metal pad, it should be NG in most factory but cheap PCB provider do not care that. It will increase cost for the low yield rate.
2. The impedance matching, cheap PCB provider do not have that. That will effect RF, USB and DDR, sometimes it will slow down data transfer speed, sometimes it can not work at all.
3. SMT quality, cheap factory uses cheap machine, increase cost because low yield rate.
4. Low quality chips. Some chips are incredible low price, the small batch even lower than mass order especially on alibaba & 1688 & taobao), the recycle ones normally are from junks, the chips’ pads are oxidized, maybe pass test in factory but once you use it with heavy load, the heat will broke them. For my production, must and only use new chips(out of chip factory < six months with vacuum packaging) from the top provider or directly from its maker.
PS: that’s why a lot of cheap production from ShenZhen only have a short life. That is very very bad and dishonest.
And many many details are not in books and hard to show in blog, they are the experience of an engineer.
That is still NOT the end…opensource hardware do not include:
- get contact with good providers(digikey and mouser do not have everything)
- a test application to test the production
- a test jig to test the production
- calibrate the RF, need special device and application
- Not Good production, need to repair.
PS: every steps cost a lot of time + money.
That’s Why NOT Open Source Hardware:
A REAL COMPLEX hardware can not be simply open source as software, it is an art of production, need time to try, to make mistake, need a lot of sweat and not a simple copy&paste.
I just want to public SCH and PCB could help people understand how it works, makes it easy to develop daughter board base on it, but not suggest directly copy from it.
ONE THING FOR SURE: VoCore and VoCore2 are ALWAYS OPEN, but never an open source hardware.