| 摘要 |
PURPOSE:To prevent the reflection of a transmission signal waveform by using a bonding wire having a prescribed inductive component for each bonding wire and matching an input/output impedance viewed from each package terminal respectively to the characteristic impedance of each transmission line. CONSTITUTION:A prescribed value is selected to an inductane L of a bonding wire 3, a circuit comprising a capacitor 6 and a resistor 7 is provided between an input/output pad 4 and a ground terminal so as to match the input/output impedance viewed from a package terminal 2 with the characteristic impedance of the transmission line 1. The capacitor 6, the resistor 7, a parasitic capacitance Cs of the terminal 2 and the inductance L of the wire 3 form a pi-type impedance matching circuit. Since the parasitic capacitance Cs of the terminal 2 varies with the mounting state and the manufacture tolerance of the package, the capacitance of the capacitor 6 is adjusted to match the impedance. Thus, the reflection of a transmission signal waveform is prevented to improve the frequency characteristic and the pulse response waveform in a treated signal band.
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