5V 3A USB charger BY-D0500200C

DSC_8646

Official specifications:

DSC_8645

DSC_8647 DSC_8648 DSC_8649

DSC_8650 DSC_8651



Measurements


5V%203A%20USB%20charger%20BY-D0500200C%20230V%20load%20sweep

The charger is rated at 3A, but can deliver more than 4A. The output voltage is on the high side.

5V%203A%20USB%20charger%20BY-D0500200C%20120V%20load%20sweep

When running on 120VAC the maximum current drops a bit.

5V%203A%20USB%20charger%20BY-D0500200C%20230V%20load%20test

No problems running one hour at 3.0A.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp4117

M1: 75,2C, HS1: 77,6C
HS1 is probably the transformer, M1 is the rectifier diodes.

Temp4118

HS1: 77,1C
Here HS1 is the two rectifier diodes.

Temp4119

M1: 54,2C, HS1: 79,5C
HS1 is the transformer.

Temp4120

M1: 51,5C, HS1: 57,8C

Temp4121

M1: 72,7C, HS1: 75,0C

10ohm

At 0.5A the noise is 10mV rms and 133mVpp.

5ohm

At 1A the noise is 10mV rms and 100mVpp.

2ohm

At 2.5A the noise is 8mV rms and 97mVpp. generally the noise is very low.



Tear down

DSC_9395

Some pressure from my vice made the seam crack and I could break it open.

DSC_9396

At the mains input is a fusible resistor (FR1 gives that away) covered in heatshrink. There is a common mode coil (LF1) and the switcher is a CR5244Y.
At one side of the tranformer is the blue safety capacitor and a inductor, on the other side is the opto coupler and two rectifier diodes in parallel.

DSC_9398

One this image the common mode coil, the safety capacitor and the output inductor can be seen.

DSC_9399 DSC_9401

On the first image the fusible resistor can be seen between the two input connectors. The switchers is not mounted flat on the circuit board.
On the second image the flying leads from the transfor is easy to see.

DSC_9400

Here the two rectifier diodes and the opto coupler can be seen. The switcher ic is just below the revision mark.

DSC_9397

On this side of the circuit board is the bridge rectifier (BD1) and the voltage reference (U3).

DSC_9402


DSC_9403

Safety distance is good.

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



Conclusion

This power supply looks fairly good, with low noise and lots of current, but I would have like the current limit a bit closer to the 3A mark. The high voltage is nice for some application, but it would have been better if it was closer to 5.25V



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?