Offline burning and Online burning of PCBA program

PCBA processing technology has become increasingly mature, with a wide range of applications, and it plays a key role in various intelligent equipments today. In order to make the circuit board to achieve the intended design function, in addition to the hardware, the matching support of the software/program is indispensable. Then the question is: program can run through the IC, but how can it be "moved" into IC?

The answer is "burning". Burning, also know as programming, it is the process of moving the program into the internal storage space of the chip, is generally divided into offline burning and online burning.

Offline burning

Compatible with different packaged chips through various adapters, and only when the chip and the adapter are matched together can the program be burned. The adapter itself is a precision fixture, and different chips and different packages require different adapters.

At present, the packaging of chips such as eMMC, is developing in the direction of miniaturization and planarization such as BGA and QFN packaging, and the price of adapters of this type of packaging is not low.

The disadvantage of offline burning is, if there is an error during the production test, the chip need to be removed from PCB board and re-programming in accordance with the prescribed process, which is time-consuming, laborious, and costly. There will be some unexpected situations during PCBA processing and production, such as insufficient temperature resistance of the circuit board, and the chip will be damaged when the chip is disassembled, which will increase the risk of scrap.

Online burning

Online programming uses the chip's standard communication bus, such as USB, SWD, JTAG, UART, etc. The interface is generally fixed, and there are fewer pins that need to be connected during programming. Because the interface communication rate is not high, the programming can be completed by using ordinary wires without high consumption.

Since online programming is performed by wire connection, if an error is found during the production test, the PCBA that has error can be found immediately, and the program can be re-programmed without disassembling the chip. It not only saves production costs, but also increases the efficiency of programming.

More importantly, the PCBA production line is also developing towards automation. More and more manufacturers add ICT, FCT and other functional testing machines to the production line. The production method of using automatic fixtures and online programming can be performed in the programming process. Save the manual operation, burn directly after mounting the board, and then send the PCBA to the testing machine for testing. The entire production process is fully automated, which can greatly improve production efficiency.