UK A1299/S1000

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Official specifications:
I got this charger from fasttech

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No retail package for this charger, I got it in a envelope.

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With the large plug size UK uses, the charger fits inside it.


Measurements



UK%20A1299%20load%20sweep

The adapter is rated for 1A and it can nearly deliver, but it has no overload protection.

UK%20A1299%20load%20test

It could supply 0.95A for one hour.
The temperature photos below are taken between 30 minutes and 60 minutes into the 1 hour test.

Temp1656

M1: 35,7C, M2: 36,9C, HS1: 57,8C
Looks like it is one part inside the charger that is the main heat source (The output rectifier diode).

Temp1657

M1: 38,7C, M2: 50,3C, HS1: 57,2C

Temp1658

M1: 42,0C, M2: 31,1C, HS1: 43,1C

Temp1659

M1: 34,2C, HS1: 51,3C

5.5ohm

At full current I have 144mV rms and 860mVpp noise, this is not very good.

10ohm

Reducing the load to 0.5A gives 91mV rms and 430mVpp, again rather high.


Tear down

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Pressing on the charger with a vice and the bottom pops open.

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This charger uses a bridge rectifier and has a power transistor do drive the trafo.

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Notice the serpent trace where the mains input is connected, this is supposed to be a fuse.

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The isolation is rather bad it is supposed to be over 6 mm on the circuit board, but here it is about 0.5mm



The charger failed a isolation test with 2500 volt, this makes it doubtful to use with 120VAC mains.



Conclusion

Another cheap charger with very bad safety, stay away.



Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger