Kuulaa PD+QC 36W KL-CD06

DSC_1874

Official specifications: I got it from Aliexpress: kuulaa Official Store

DSC_1872 DSC_1873

It arrived in a Kuulaa plastic bag inside a plastic envelope.

DSC_1875 DSC_1876 DSC_1882

DSC_1878 DSC_1880

DSC_1879 DSC_1877




Measurements

Kuulaa%20QC5V%20120V%20load%20sweep

It can easily deliver the rated 3A on the QC output.

Kuulaa%20QC9V%20120V%20load%20sweep

And nearly the rated 2A for 9V

Kuulaa%20QC12V%20120V%20load%20sweep

At 12V it can only deliver about 1.3A and not the rated 1.5A

Kuulaa%20QC12V%20230V%20load%20sweep

Using a 230VAC supply it can easily live up to its rating.

Kuulaa%20PD5V%20120V%20load%20sweep

The PD output can deliver 3.5A at 5V

Kuulaa%20PD9V%20120V%20load%20sweep

At 9V it is slightly below the rated 2A.

Kuulaa%20PD12V%20120V%20load%20sweep

At 12V it is again below the rating.

Kuulaa%20PD12V%20230V%20load%20sweep

Using 230VAC it can easily live up to its rating.

Kuulaa%20230V%202A%2B1.5A%20load%20test

I did the one hour run at 230VAC using 9V and 12V output, this only worked for about 10 minutes.

Kuulaa%20230V%201.5A%2B1A%20load%20test

Reducing the current some improved the runtime to 20minutes

Kuulaa%20230V%201.5A%2B0.8A%20load%20test

After reducing the current a bit more I could run it for one hour.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp7528

M1: 70.6°C, M2: 59.3°C, HS1: 71.1°C
The two hot spots (HS1 & M1) are the two switcher chips.

Temp7529

M1: 64.2°C, HS1: 66.4°C

Temp7530

M1: 66.0°C, HS1: 67.0°C

Temp7531

M1: 54.0°C, HS1: 58.2°C
Here the hot area is partially due to the transformers.

Temp7532

M1: 55.1°C, HS1: 70.1°C

10ohm

At 0.5A the noise is 97mV rms and 1121mVpp.

5ohm

At 1A the noise is 47mV rms and 917mVpp.

2ohm

At 2.5A the noise is 79mV rms and 917mVpp.

10ohmQC9V

At 9V 0.9A the noise is 69mV rms and 1138mVpp.

10ohmQC12V

At 12V 1.2A the noise is 68mV rms and 1121mVpp.

10ohmPD5V

At 5V 0,5A the noise is 24mV rms and 953mVpp.

2ohmPD5V

At 5V 2.5A the noise is 76mV rms and 970mVpp.

10ohmPD9V

At 9V 0.9A the noise is 32mV rms and 1200mVpp.

10ohmPD12V

At 12V 1.2A the noise is 37mV rms and 1306mVpp. There is a lot of peaks in the noise, probably common mode noise from bad mains filtering.



Tear down

DSC_2643

I put some pressure on the enclosure with a vice and could then break the bottom away with my fingers.

DSC_2644

The circuit is two nearly identical switch mode supplies, only difference is the output capacitor that is 1000uF for the QC and 470uF for PD. The only common part between the two are the input fuse (F1)

The QC controller (FT41NR) is placed next to the USB connector, the PD controller on a small circuit board.

DSC_2646 DSC_2647

DSC_2648 DSC_2649

DSC_2645

On this side is the bridge rectifiers (DB1 & DB2), one for each switcher, the opto feedback (PH1 & PH2) and the references (IC4 & IC5: 431).

DSC_2651

1

The PD controller has a PD chip (U1: FP6606C) and a MOS transistor to switch the output on/off.

2

DSC_2650

The distance across the opto coupler is only 4.5mm, this is way below the requirements.


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




Conclusion

At 120VAC it cannot deliver rated power and it can never deliver rated power for longer time. The supply is also a bit limited with PD, where the maximum is 12V, not 20V.
The isolation distance between mains and low volt side is on the low side, especially for 230VAC.




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?