Carprie Dual USB Car Charger

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This is a VERY cheap car charger, I paid less than $1 including shipping from China.

Official specifications: I got it from Aliexpress dealer: SuperAutoMaker Shop Co.,LTD Store

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No fancy box for this charge, just an envelope and a plastic bag.

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The plastic and construction feels very cheap. The USB connectors are not very good.

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Measurements

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The 0.5A coding is fairly correct for this charger, it can not deliver more than 0.65A here.

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With 24V input the output can deliver 0.7A, still a long way from the rated 2.1A

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The secondary output is the same.

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And it is also the same when running the two outputs in parallel.

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With a 0.6A load the input must be above 14V to maintain 5V output, this is a very bad design.

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The idle power consumption is low.

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There was no problem running 1 hour with 0.5A load.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp6296

M1: 33.8C, HS1: 51.5C
The temperature is fairly low, due to the low current.

Temp6297

M1: 40.6C, HS1: 42.0C

10ohm

At 0.5A the noise is 13mV rms and 83mVpp, noise is low, but the current is also low.




Tear down

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I did not need any tools to take the charger apart, first I pulled the front off, then I could take the two pink pieces apart.

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There is not many parts in this charger. The main IC is AD84064 and it mostly follows the schematic from the datasheet, but input capacitor is much smaller.

M1

The logo on the chip looks like Texas Instruments, but the Chinese datasheet do not say anything about that.
The chip is rated for 0.7A output with 12V input and designed for weak usb chargers.

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The input capacitor is 25V rated, a 24V car system have up to 30V, that would not be safe.

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Only the led is on this side.

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Being a 12V device there is no need to test with high voltages.



Conclusion

The only surprise with this charger was the low noise, the old style coding and lack of any real power was as expected. The charger is not for 24V systems.

It is not a good charger for any modern phone, but it mostly works for low currents.



Notes

Read more about how I test USB power supplies/charger
Compare car chargers and other DC supplied chargers