And this seems to be the only function of the 3.3V regulator (besides the 3.3V pin on the SPI connector). The problem is that any memory you fit in the socket will be powered from 3.3V. The chip is powered from 5V, so its I/O ports will also use 5V. Now, let's return to the schematic and analyze it a bit. Their product page offered a the PCB design of the device (only top side, however).ĬH341A Mini Programmer PCB (by WAVGAT/AliExpress)

I also found WAVGAT store (a seller on AliExpress). Schematic of the black CH341A Mini Programmer The schematic is quite simple, based on datasheet.

I took the multimeter and started to trace lines on the programmer PCB until I got a complete schematic. It didn't have the pinheaders on the sides of the ZIF socket which I wanted to know what they are for. SchematicĪfter some searching I found a schematic of a CH341A based programmer, but it wasn't exactly right and complete. The programmer can be bought with additional sockets and adapters, some of them with voltage shifting circuits. Photo of the black CH341A Mini ProgrammerĪ quick look at the board reveals the main electronic parts used: CH341A, a 12 MHz crystal required by the chip, a 3.3V regulator, two 7 pin headers and the ZIF ( zero insertion force) socket. But, first of all, let's have a look at the hardware. There are open source applications that support this programmer. Also, some source codes are available from manufacturer. Drivers are available from manufacturer's website (but the site is written in Chinese). The problem with these devices is that you get them without any documentation or software. A popular device is the black CH341A MiniProgrammer that you can buy for 2 to 5 USD. The IC is somehow limited in this configuration, because the programmer makes use only of the SPI and I 2C interface and leaves a lot of pins unconnected. CH341A is used by some cheap memory programmers. The chip is manufactured by Chinese company Jiangsu QinHeng Ltd. An overview of CH341A devices with driver and tools download linksĬH341A is an USB interface chip that can emulate UART communication, standard parallel port, memory parallel port and synchronous serial (I2C, SPI). Take a look at the schematic of this versatile programmer to learn how to use it properly.

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