Am 15.10.2018 um 18:02 schrieb aTc atc@k-n-p.org:
On 10/15/18 11:33 AM, H. Nikolaus Schaller wrote:
- (broken board?) noticeably draining the battery while off (older
unit doesn't do this)
Do you have a rough estimate how fast it drains? This could help to exclude some components.
My board also has this, and it's a slightly older 2gb one. It drains the battery from 100% to 0% in about a day.
Oops. That would be 6000mAh in 24h = 250 mA...
This would also be ca. 875mW - something that should clearly be visible in a thermo camera.
No idea what can draw that much when Palmas is powered off.
Well, there are consumers on VSYS which could become active with Palmas off: * HOST ports - but they need a short circuit at the 5V output to draw that much * 3G/4G modem - should not need more than 10mA if it remains on unplanned * Headset multiplexer - hm... * WiFi module - has a separate power enable controlled by the OMAP5 (pulled low if OMAP5 is powered off) * Keyboard backlight - is a PWM from OMAP5 * display board - should also be turned off if there is no control from OMAP5 * DC/DC converters for SD cards
So it is difficult to say without directly measuring a board. Maybe ED has one where he identifies this effect. And can look at it through a thermo camera.
I can do some more accurate timing if you want.
The method used to shut down the pyra doesn't seem to make any difference (software poweroff or holding the power button for 8+seconds).
Both just shut off the Palmas but not necessarily other components.
BR, Nikolaus