Circuit board manufacture

摘要

To determine the stabilized surface insulation resistance (SIR) of a printed circuit board substrate, a test printed circuit board is provided which has desirable clean surface conditions. This surface bears a predetermined circuit board test pattern and has a known SIR characteristic resulting in a known stabilized SIR. The test board is then subjected to a soldering step which is performed in the same in-line production with commercial boards. After the soldering step, the SIR characteristic of the soldered test board is determined for a time period sufficient for a comparison with the SIR characteristic of the clean test board to enable the stabilized SIR of the soldered test board to be determined.