There are several reasons I will not use a Next Thing Co. C.H.I.P in another project.
- Shoddy design – I received my Kickstarter C.H.I.P finally only to find that it reboots when a keyboard is hooked up to it. This isn’t some fancy keyboard, but a very basic USB keyboard (yes it does have a HUB in it – but how else would I also plug a mouse in). The USB spec provides for a minimum of 500 mA @ 5V DC. With a 2A 5V power supply I had power issues with C.H.I.P rebooting. Within 2-3 keypresses of trying to enter my WiFi password C.H.I.P reboots. I did manage once to get the wireless setup before it rebooted (with the help of a LiPo battery plugged in). I’ve also tried power supplies up to 5V 3A with simillar issues.
- Charging circuit on my unit appears defective. Yes C.H.I.P. let me set the SSID but basically continually drained the battery even though I was plugged into wall power. This took my battery down to the cutoff point after a couple hours. In addition my AXP209 power management IC gets to about 130+ degrees F which is uncomfortable to the touch, without the battery even plugged in. I’m guessing that this is the reason for the brown-outs and the lack of battery charing. It also doesn’t instill the feelings that this is even a remotely power efficient design. If it’s dumping 10% of the supply current into a charging circuit that’s not being used that’s a problem.
- Customer Support – This is where companies can shine or fail miserably. Best case scenario there is a great FAQ or documentation for the product and one never has to e-mail support. None of these apply to NTC. While they do have a Wiki it’s sorely lacking in information. The first response from customer support is to look in the “BBS” forums or the online documentation. The documentation I could find states “any single cell (1S) 3.7V Lithium Polymer (LiPo) battery” with a JST connector can be used. That being said their support staff said my Single Cell 1S 3.7V LiPo battery (650mAH) might not be compatible. I’m well aware that this battery won’t run C.H.I.P. for long but it should run for 10-15 minutes without the supply hooked up allowing for a more graceful shutdown. I guess “any” in the description of what batteries work is not true.
- Peripherals and Connectivity – The single USB port lets you connect only a single device, likely a keyboard or USB powered hub. This results in the necessary addition of a secondary power supply for the hub. In addition the only output (stock) on the C.H.I.P. is composite video. While it works, it doesn’t work great and is fairly blurry even on a good display. Having a stock HDMI instead of composite would have been nice…but for $9 bucks what can you expect. Oh wait, the $5.00 Pi Zero has HDMI.
- Cost, while they do sell C.H.I.P. for $9.00 in the long run it ends up costing more. Expect to spend $7+ on a suitable power supply and another $15-20 if you want video out better than composite. Yes you need a good power supply for the PI as well but I haven’t had any problems with my existing stash of high-current phone chargers. That already puts you into the price range of a Raspberry Pi 3 and then you only have half the memory and a slower processor. While it does have 4 GB of on-board flash storage the cost of an SD card (8 GB for < $4) isn’t worth the frustration of dealing with the Chrome based flash tool. And you can add more storage to the Pi easily without utilizing the one USB socket on the C.H.I.P. with a larger SD card. There’s no way to add more storage to C.H.I.P. other than utilizing the single USB port.
- Default configuration of the charge controller. Again I don’t know if this is because my board is defective. But after a couple hours of the AXP209 dumping 200 mA through who knows what (I seems to thing there is a battery when there isn’t) it finally gives up. At this point the power consumption drops down to reasonable levels of around 400mA while sitting idle. I would imagine that at boot it wouldn’t immediately be configured to dump current into the battery – because a lot of power is consumed while booting.
Because of support wasting my time and the issues I’m having with my Kickstarter C.H.I.P. I have to say my next project will be utilizing a Raspberry Pi Zero, Orange Pi or full-blown Raspberry Pi. Time is money my friends and I wasted a couple hours of my time and $9 on this one already ($15 if you include the LiPo battery it killed). All I wanted it for was a triggered video playback and I can’t even get it to the point where it will even run reliably sitting idle. The kicker is support says I need a larger battery even if it’s plugged into power. Do yourself a favor and grab a much more robust Raspberry PI. You won’t regret your decision.