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I planned to add the chinese NoIR RPi camera in a birdhouse. First tests revealed, that the camera module heated up to 65 ⁰C. The IR LED's were very warm too.

How much power is dissipated by the original RPi camera in comparison to the the chinese clones? What are the environmental operation conditions? Can a IR sensitive camera work well, if the chip heats up that much?

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    Ask the third-party manufacturer. Nothing to do with the Pi. – joan Mar 13 '18 at 22:30
  • @joan I am interested in the original cam data. I made the sentence bold for you. – Jonas Stein Mar 14 '18 at 0:10
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    How much power is dissipated by the original RPi camera ... what research have you done? – jsotola Mar 14 '18 at 2:03
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According to the Specs

The official documentation doesn't actually contain a power spec. https://www.raspberrypi.org/documentation/hardware/camera/README.md

The FAQ's do offer some guidance: https://www.raspberrypi.org/help/faqs/#power

The Camera Module requires 250mA

This is measured as additional current from the 5V supply.

Calculating the Power

Ohm's Law says: Power = I * V (current times voltage) so P = 0.25 * 5 = 1.25Watts.

The above answer is likely the maximum power the camera uses when in operation, so an upper bound. This isn't a bad question especially if you're trying to build a solar powered pi. It's woefully difficult to find this basic information online!

In Practice

According to one of the Raspberry Pi engineers and forum moderators Source: https://www.raspberrypi.org/forums/viewtopic.php?t=152864

the original Pi Camera board v1.3 camera takes about 200-250mA.

Assuming that's measured off the 5V USB input to the Pi, you could assume 5*.25 = 1.25W power usage maximum, and 5*.20 = 1W minimum in use.

Component Analysis

The Pi camera 1.3 is based off the sensor by Omnivision the OV5647, BOTH for the regular and NOIR versions.

According to GoPhotonics, the sensor itself draws 96mA from a 3V input. https://www.gophotonics.com/products/cmos-image-sensors/omnivision-technologies/21-118-ov5647

However there's likely a voltage regulator in the camera circuit using more power (i.e. turning 3.3V on the Pi CSI connector to the 3V the sensor needs).

Note: the "NOIR" means a small filter which filters out IR from the sensor, has been removed. That is a mechanical change, and shouldn't affect the power draw. So we expect power usage to be the same between regular and NOIR versions.

How to get a better answer

As far as comparing to the 'knock-offs' - my recommendation would be to see whether your flavor of knockoff is using the OV5647, and then get a basic USB inline ammeter and report back to us! e.g. like this (click for full size):

USB Ammeter

https://www.amazon.com/dp/B019RHJRM8/ref=asc_df_B019RHJRM85402504/?tag=hyprod-20&creative=395033&creativeASIN=B019RHJRM8&linkCode=df0&hvadid=242041198988&hvpos=1o1&hvnetw=g&hvrand=15918663062740235728&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9031637&hvtargid=pla-426269107564

  • Nothing on the Pi board is powered by 5V, except USB and the 5V supplied to HDMI. Most use 3.3V, supplied by the on-board regulator. – Milliways Mar 14 '18 at 5:52
  • I understand that nothing on the pi is powered off the 5V - I'm trying to explain the context of the quote of the 200-250mA that I referenced. I'm pretty sure the engineer wasn't measuring that current across the camera module itself, but rather measured as an increased draw from whatever was powering the pi + camera module. I tried to clarify with an edit. – Kelton.Temby Mar 14 '18 at 6:30
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    @Fabian I agree - I picked up 30 of the $4 clones on alibaba the other day (I run 86 pi's these days....). So far haven't had any quality issues with them. It would be nice to study them more carefully, but since we don't really have a good baseline it's hard to say. I do still have a few of the original cameras ordered through MCM that I could do a side-by-side with if I had a nice power lab power supply... but I don't currently have access to one – Kelton.Temby Mar 14 '18 at 6:31
  • @Fabian updated answer with a tool to compare the clones! – Kelton.Temby Mar 14 '18 at 9:21
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    Thank you @uhoh I accepted your improvement! My assumption from the GoPhotonics spec is that the draw should be significantly lower in standby: Power Consumption : Active: 96 mA, Standby: 20 µA However, if a voltage regulator is being used on the clone board that's always burning the 3.3V, it could still be drawing something similar. Since I'm currently working on a solar project with this question in mind, I'm going to get that device in the pic and test as well! – Kelton.Temby Mar 14 '18 at 9:47

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