YwRobot PCB Power supply (junk)!

I’ve had this YwRobot PCB Power supply module for a while now, and I’ve been disapointed since I got it. At first I was realy excited to use it with my breadboard. The module helped clean up an already busy breadboard by reducing the extra wiring coming from a buck converter dangling loose on the work table. The YwRobot PCB Power supply is suppose to output 5V and 3.3V at the same time which was a great addition for any prototyping which typically need 5v, 3.3v or a combination of both.

When powering up this little board with an Arduino Nano it made a nasty cracking sound… the Arduino Nano was dead… Luckily the Arduino Nano can be rescued most of the time by just replacing the diode underneath… Fixed the guy up, test it on its own using USB cable – all was fine. Plug it back into the breadboard and power it up, and then BOOOM!! Just kidding, that same crackling sound, and it was dead again. Again the Arduino died. So now I was suspecting something is causing too much voltage over the Arduino’s power.

Unplugged the dodgy YwRobot power supply from the breadboard to test on its own. Testing the outputs and I noticed that that 5V output is about 1V less than whatever the input voltage is 11 volts in my case! No wonder the unlucky Arduino didn’t last. The 3.3V still looked fine. Googling a bit and I found many other people have the same issue with the device where when it fails it fails in such a way that the input voltage is put on the output (see links below).

I would not recommend this YwRobot PCB Power supply to anyone. It is really cheap and really crappy and seems to fail very easily, even when just running some idle components. It fails in such a way that it can damage your precious components.

See also other forums with this issue

• https://www.reddit.com/r/arduino/comments/3ti1me/beware_of_this_breadboard_power_supply_ywrobot/
• http://ik1zyw.blogspot.co.za/2015/03/breadboard-power-supply-module.html