Pascal is correct. The designs I have seen use the A/D channels on the
UCB1400 for things
like battery management, supply monitoring etc. The digital IO is usually
used for things like turning the backlight of an LCD display on/off and
enabling/disabling voltage regulators for various peripherals etc.
[mailto:gumstix-users-admin@...] On Behalf Of Pascal A.
Sent: Saturday, March 25, 2006 9:14 PM
Subject: Re: [Gumstix-users] Audiostix II -R781
Gordon Kruberg writes:
> - Similarly, how about an optional jumper between V_BATT and AD0 ? (The
> UCB400 has internal resistive voltage dividers on ADx.) > Not done,
subject to my understanding a bit more about the goal.
> Question I have is whether this was really for V_Batt (vs. AVdd or Vcc)
Section 11 of the UCB1400 datasheet says "... This makes these analog inputs
very suitable to monitor battery voltages."
Section 15 says the input range is 7.5 V.
Disclaimer: I haven't actually tried it. But it looks like these inputs are
really intended for battery monitoring. The idea would be to allow a system
to do something before the CPU is undervolted or before LiPo batteries get