| 摘要 |
PURPOSE:To reduce the area for fixing a capacitor, make a wiring pattern for connecting the capacitor with a power supply and connecting the capacitor with a ground line unnecessary, and miniaturize an element, by fixing a parallel plate type capacitor on the central part of a package, on which a photodiode is mounted. CONSTITUTION:A parallel plate type capacitor 2 is soldered (gold tin) to the central part of the upper part of a package 1, and a preamplifier IC 4 is soldered to the peripheral part. The bottom surface of the preamlifier 4 and the bottom surface of the parallel plate capacitor 2 are directly fixed to a case, and have the ground potential. A photodiode power supply pin 11 is connected with the upper surface of the parallel plate capacitor 2 through a wire 21. A preamplifier power supply pin 27 is connected with a power supply pad of the preamplifier 4 through a wire 28. Thereby the mounting area can be reduced, so that an element can be miniaturized. |
