[Arm-netbook] flying squirrel 7in tablet: 2nd PCB layout attempt

luke.leighton luke.leighton at gmail.com
Mon Jan 21 20:51:47 GMT 2013


On Mon, Jan 21, 2013 at 7:14 PM, Ken Phillis Jr <kphillisjr at gmail.com> wrote:

> Although, it's also possible that the person will most likely be
> making use of the video decoders to decode a video from the sdcard. I
> would personally like to have decent playback using xbmc.

 ooo, we'll have to see about that: bit of an experiment going on here
with the audio.  i expect it to be ok: 1mhz PWM flattened with an RC
circuit and feeding a cheap-and-cheerful 0.5W amplifier chip that's
normally found in gazillions of radio alarm clocks should do the job,
eh? :) [1]

> As for the actual power source, I'm guessing that the power source
> will be any standard 5v that can provide about 1amp should be more
> than enough.

 naah i believe it has to be around 2A, you're not just charging the
battery you'd also be powering the device.  and i think it can be a
bit more than 5V, iirc correctly from the AXP209 datasheet.

> Normally I would agree, but the falling risk is actually something
> that is a high risk for tablets of this type especially when the
> tablets are used to read books at night like a kindle. The only reason
> the kindle doesn't break as often is that the kindle based devices
> have extremely long battery life that can be anywhere from 10 days to
> 30 days.

 yeah cos they change the state of the little mechanical balls, flip
them with electromagnets, and then the device goes right back to
sleep: it's hardly using any power at all.  i think if you sat there
going "flip-flip-flip" for a few hours, then if you didn't get
screaming RSI....

 people have tried doing rock-hard robust power connectors: all that
happens is that an accident destroys the PCB.by ripping that entire
corner off, along with the connector.

 i'll try to persuade the client that following what samsung did for
the chromebook (separate tiny PCB for the connector) is a really good
idea.

l.



More information about the arm-netbook mailing list