QC4.0 PD DC-DC 6-30V Step Down Buck USB-A USB-C Charger


A Fast USB charger that takes a DC voltage between 7-30V

In stock

SKU: DOWN-QC4 Categories: ,



A Fast USB-C or USB-A charger that takes a DC voltage between 6V and 30V


Charging mobile phones, tablets, power banks, anything that can be powered from USB
Fast charging devices can negotiate higher power and faster charging


Connect a DC voltage by soldering wires to the two holes with enough power to supply the output.  The input voltage must be higher than the output voltage.  Plug in a USB cable to either or both of the ports and connect to your device.


Input voltage between 6V-30V DC
Output voltage only observed at 5V and 9V.
Max observed power 18W
Small Blue LED indicates power is connected
Small Red LED indicated quick charge tech is employed
Quiescent current of 2-3mA when no USB device connected depending on input voltage
Supports the following fast charging protocols:

  • QC2 & QC3.0: Android Mobile Phone Using Qualcomm Mellon Processor
  • FCP: HUAWEI/glory9V2A Quick charge
  • Apple: Apple 5V 2.4A Quick charge
  • AFC: Samsung mobile phone, IncludeS9/note9 other flagship
  • MTK PE: Red rice, Melanie and other mobile phones using MediaTek chips

Protection includes

  • Reverse input connection without shorting
  • Output overcurrent protection
  • Input overcurrent protection


The heatsink keeps this little charger cooler than other chargers.  TODO Measure temp at 5V 2A out
The heatsink does get hot at 2A, so it requires some ventilation
Input current must be enough to supply phone’s requirements or the charger won’t stabilise
This supplies 9V to a powerbank I have.
My Lenovo Tablet with USB-C charges at 5V 1.95A


2nd Class Royal Mail Small Parcel, or you can level up to 1st Class.
Dispatched same weekday if ordered before 3pm.  I hold all my stock in Surrey.


My support is second to none.  Check my feedback.  I will gladly help you before or after purchase.  I love power supplies!
I’ll gladly refund you if it’s faulty or you can return it working if it doesn’t perform as you expect.
Be careful with clone UK suppliers – they’re quite often drop-shippers who have no idea what they’re selling – just check their feedback.



Additional information

Weight 0.009 kg
Dimensions 3.8 × 2 × 0.8 cm

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