How to Check if Prolific USB-to-UART Adapter is Fake

UART (Universal Asynchronous Receiver-Transmitter) interface is often used by various electronic devices like modems, routers, smartphones, tablets etc., to communicate with other devices in the absence of an operating system. If your device is bricked and is not being detected by PC then you can connect it to your PC through a simple USB-to-UART adapter and flash the firmware to make it work once again.

There are mainly two different types of USB-to-UART adapters available in the market today – the ones that use Silicon Labs CP210X chips and the others that use Prolific PL2303 chips. According to Prolific website, the online and offline market is filled with fake adapters that use cheap non-Prolific chips but have Prolific label on them. These fake Prolific chips are somewhat compatible with the Prolific drivers but may not work as expected or may fail to work at all.

If you have bought a USB-to-UART adapter from one of the online stores and want to know if you have bought a product that uses a genuine Prolific chip then you can use the Prolific PL2303 chip checker tool. Here is how:

  1. First of all download and install device drivers for Prolific PL2303 USB-to-UART adapter from http://www.prolific.com.tw/US/ShowProduct.aspx?pcid=41&showlevel=0017-0037-0041.
  2. After the installation, attach the USB-to-UART adapter to your PC. Wait for Windows to recognize the device (you will hear “tada” the sound that Windows makes when you connect a USB device).
  3. Open Device Manager by pressing Win+R key combination, typing devmgmt.msc and pressing Enter.
  4. In the Device Manager, find Prolific USB-to-Serial Comm Port. It will be under Ports section. Note down the COM port number it is using. In the following screenshot it is using COM3.PL2303 Chip Checker
  5. Download PL2303 Chip Checker tool from http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=225&pcid=41 and launch it.
  6. Select the COM port as you noticed in step 4 above and click on the Check button. If you are using a fake product, then it will show a message – No PL2303 Chip. Otherwise, it will show the chip name and variant.PL2303 Chip Checker

This way you can find out if you have ended up with a product that uses a fake PL2303 chip or not. If you use a product having fake PL2303 chip then it can give unexpected results and can even cause damage to the device you are interfacing with.