Flowme QC3 USB charger JYX-218-QC

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Official specifications: I got it from aliexpress dealer: FLOVEME Fashion Accessories

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It arrived in a plastic bag inside a plastic envelope without any accessories.

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Measurements

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The overload protection is very high at 5V output. The voltage looks nice (Slightly above 5V).

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At 9V the current limit is 3.5A, this is way above the rated 2A.

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At 12V it is about 2.8A, again well above the rated 1.5A

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With 120VAC supply the current limit goes down to about 2.5A for 12V

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For a load test I used 9V 2A load for one hour, it worked fine.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp6877

M1: 42.6C, HS1: 67.2C
HS1 is the transformer.

Temp6878

M1: 40.2C, HS1: 56.5C

Temp6879

M1: 74.6C, HS1: 79.0C
HS1 is the transformer and near M1 is from the the rectifier diode.

Temp6880

M1: 68.7C, HS1: 71.6C
Again the transformer and the rectifier diode.

Temp6881

M1: 37.2C, M2: 54.7C, HS1: 67.3C

10ohm

At 0.5A the noise is 17mV rms and 124mVpp.

5ohm

At 1A the noise is 28mV rms and 191mVpp.

2ohm

At 2.5A the noise is 42mV rms and 253mVpp.

10ohmQC9V

At 9V 0.9A the noise is 30mV rms and 216mVpp.

10ohmQC12V

At 12V 1.2A the noise is 58mV rms and 454mVpp.




Tear down

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Mounting the bottom in my vice and whacking the top with a mallet was enough to open it.

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At the mains input is a fuse (F1) covered in heat shrink, between the mains capacitors (C1, C2 & C3) is a inductor (L1). The switcher IC (SW1) is covered in a small heatsink. There is a safety capacitor (CY1) and a opto coupler (U2) to the low volt side.

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On this side it the bridge rectifier (BD1) at the mains input, on the low volt side is a rectifier diode (U3), the QC controller (U4: FT4) and the reference (U5: 431).

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The distance between high volt side and low volt side must be above 6mm, it is more like 5mm here.



Testing with 2830 volt and 4242 volt between mains and low volt side, did not show any safety problems.



Conclusion

This USB charger works fairly well with support for a couple of fast charge protocols, safety is not perfect and it can deliver too much current.




Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?