Re: **LOW** Power applications


Giorgis wrote:
linnix wrote:
Ken Smith wrote:
In article <1157206910.811924.308320@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
linnix <me@xxxxxxxxxxxxxxxxxx> wrote:
[...]
If time is not absoulely critical, you can use the internal RC. Set it
to 32KHz regularly and boost it to 2MHz (for 19200 baud) for data dump.
You also need to switch off the RS232 drivers (eg. Max232), since it
draws 10mA all the time. You can log the start and end real time to
recalibate your data stream.

I would advise against using any Maxim part. In this case, you may be
much better off making your own RS-232 driver. An RS-232 signal needs to
rest at -3V or more. Instead of making your own minus voltage, I suggest
you use the RS-232 signal from the PC used to read out the data as a
supply.

Oh no, I would not depend on Maxim. I am using second sources from
Sipex, ST and TI.

Guys, I am floored !!! This is looking exactly like what I want.

Would you beleave I started thinking I need an SBC and they seem to
consume about 1W. Over 12 weeks it seemed like I needed $300 of battery
with about 300 cycles before death the whole excersize looked like a
fizzer. Now It looks very possible and alot of fun

The trick is power management. At 10mA, the Max232 is drawing several
time more power than the micro at idle. I am redesigning my circuit to
turn it on only when a cable is connected (A2D the DTR signal). The
Max232 (started out at Maxim, second sources from many) is about $1,
but it requires 4 1uF caps (a penny each). Siplex actually has a part
with build in caps, but they wants $3 each.

.

Relevant Pages

  • [PATCH 18/47] updated Documentation/power/devices.txt
    ... Fixup some of the horribly ancient/obsolete description of device suspend() ... +Most of the code in Linux is device drivers, so most of the Linux power ... Most drivers will do very little; ... +power management goals, emphasizing the models and interfaces that are ...
    (Linux-Kernel)
  • Re: [PATCH 00/13] Re: Scalability requirements for sysv ipc
    ... # IPVS transport protocol load balancing support ... # DCCP Kernel Hacking ... # Device Drivers ...
    (Linux-Kernel)
  • [2.6.0] Thinkpad 390E hangs after some time
    ... I've tried to remove almost everything not needed in my kernel config, ... I disabled all Power Management etc. ... # ACPI Support ... # Device Drivers ...
    (Linux-Kernel)
  • Re: expresscard 34 media reader
    ... It definitely appears a USB Device in Device Manager. ... I right clicked on it and clicked on Properties but there is nothing as far as i can see that relates to Power Management. ... were you required to install ... I don't see any drivers on the Sonnettech site. ...
    (microsoft.public.windowsxp.hardware)
  • N00b Asks: Supporting Linux Power Management HOWTO?
    ... We're currently using kernel 2.6.11 on an ARM-based platform, ... I've already got a handful of drivers running (anyone need an I2C bus driver ... power management support into the drivers and platform-specific kernel ...
    (Linux-Kernel)