Development of LCR laser function trimming unit

Electronic circuits are now adjusted with variable inductors, trimmer capacitors, and pre-set resistors. The use of these components, however, has caused critical problems for circuit reliability because they have turning parts that generate displacement due to variation with time. We have developed a new function trimming unit that uses green laser light and enables automatic adjustment of L, C, and R with a single unit. Conventional laser trimming is performed by using the fundamental wave (1064 nm) of a YAG laser. Since the reflection factor of the YAG laser against copper is approximately 90%, it is difficult to achieve high quality trimming. We use the single trimming unit and the second harmonic generation (SHG) of the YAG laser with a lower metal reflection factor for trimming all LCR components, particularly copper foil pattern coils for high-frequency circuits