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Just a casual observation: when it is winter, my personal devices such as cellphone and Ipad consume power more quickly compared when it is in the summer.

But this could simply because of change is usage habit: staying at home more leads to using your gadgets more often.

At the same time I have noticed that the back of my Ipad heats up a lot more during the winter, which could be caused by greater power usage.

Does anyone have any insights into how ambient temperature dictates power consumption in electronics (maybe even consumer electronics)?

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    \$\begingroup\$ Does it heat up more, or is the difference between its temperature and the ambient temperature greater due to a lower ambient temperature? \$\endgroup\$ – Majenko Jan 6 '17 at 22:09
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    \$\begingroup\$ Bear in mind that the battery will perform less well at lower temperatures, hence it will not provide as much runtime. \$\endgroup\$ – Tom Carpenter Jan 6 '17 at 22:09
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    \$\begingroup\$ I have noticed that the back of my Ipad heats up a lot more during the winter, I bet that is just your perception, in winter you have colder hands so the ipad feels warmer. When used indoors, the temperature difference the electronics experience is only a few degrees. The most temperature sensitive part of a device is the battery, cold batteries cannot deliver so much power. \$\endgroup\$ – Bimpelrekkie Jan 6 '17 at 22:10
  • \$\begingroup\$ Some electronic components properties and this the devices consumption is temperature dependent but it's quite flat over normal human range. Batteries is the exception and your example with the iPhone is a good one. Lithium-ion is quite terrible below -20 degrees and I found out as late as yesterday that the Apple engineers allowed discharge (use) below -15 but not charging when I had to heat up my plugged in phone to make it stop discharging. \$\endgroup\$ – winny Jan 6 '17 at 22:13
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    \$\begingroup\$ Re your deleted "I'm working on ... adaptive control for DC converters. ... and would like to get up to speed as soon as possible." -> Go to www.piclist.com. Read/skim the somewhat clunky page. THEN go here (link at bottom of above page). Join the list. Ask your question(s) interactively. Helpful knowledgeable people will (probably) help you in an interactive friendly manner. Enjoy :-) [Ignore the "PIC" in PICList - there is a slight focus on PICs BUT people from all walks are there. \$\endgroup\$ – Russell McMahon Mar 9 '17 at 10:51
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It's the opposite, actually.

Your devices are made up of individual electrical components, while datasheet for the devices are harder to come by, we can look at component datasheets easily.

enter image description here

The above is a power consumption over temperature plot for a processor, one of the major power consumers in your devices. Most components have a positive coefficient for power consumption and temperature. Some have less linear curves where consumption is minimum at some middle value.

But for the most part, hotter devices use more power to operate normally.


As others have commented, this doesn't take into account the battery capacity when it gets cold. The lower capacity of the battery due to temperature might be large enough to make the devices seem to last less time in the cold. But, the answer of "do they consume more power when cold?" is no.

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  • \$\begingroup\$ Yes,more heat,more power consumption.That's how semiconductors work. \$\endgroup\$ – Daniel Tork Jan 7 '17 at 9:54
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Actually, they have less battery range. The major factor in cold is on the batteries. They lose a lot of capacity.

It's quite likely that your iPad "heating up a lot" is relative to ambient: it's colder outside, so the iPad feels like it's hotter. Ever go out in the cold for awhile and run your hands under "cold" 45 degree (7 deg C) water to warm up? It feels like the water is boiling hot, doesn't it.

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CMOS transistors conduct better when cold. That means they'll demand more current during switchover from Logic_low to Logic_high; that current is called "crowbar" current or "shootthru" current.

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