1 and 1903, British Hansen applied for the patent of "cable connection, improving the same connection mode" related to printed circuit boards, which was one of the earliest circuits and technologies.

2. 1936, Dr. isler of Britain put forward the concept of "P-type printed circuit", which was called "the father of printed circuit board".

3. Double panels appear in 1953.

4. Multilayer board appears in 1960.

5. At the end of1960s, polyimide flexible circuit board came out.

6. In 1970, a multilayer circuit board was produced.

7,1In the early 1990s, multilayer printed boards were produced.

JackpKilby invented the integrated circuit Before the appearance of integrated circuits, electronic devices mostly used bulky and easily damaged circuits, mainly vacuum tubes. P But in 1958, kilby invented the integrated circuit in Texas Instruments Semiconductor Laboratory, which changed the whole electronic world and made the appearance of microprocessor possible.