Extract Microcontroller code has become a quite prevail technology in the microcontroller manufacture industry. And various microcontrollers manufacturers are always discussing about how to strength their protection technology against microcontroller firmware extracting.

If a microcontroller extraction project can be divided into several parts, then extracter can place each part into different microcontrollers. Then microcontroller extracters have to reverse engineering all of the parts in order to proceed the whole process. However, this kind of method is not a applicable one for microcontroller which is budget sensitive and need to mass production into consumer electronic product.

From the design base upon microcontroller switch to CPLD or FPGA could probably a suitable choice, since extract CPLD and FPGA will require to invest more fund. Even place those unimportant parts into less secure FPGA which is based upon SRAM, it could be much more difficult than copy chip content by brute force.

Use multilayer printed circuit board and BGA package can also increase the difficulty of microcontroller unlocking, since the microcontroller is unable to monitor the interconnection internally by human eye ball. And it is impossible to access BGA directly through its interface or pinout to analysis. For the purpose of direct visiting on the lead, IC chip must be disssemble, and place it onto the dedicated test adapter with socket. Which require special tools and veterian engineers to deal with mcu cracking. besides, the footprint and package of BGA is different from DIP, SOIC and QFP, etc. its package could be more difficult to de-capsulate.