Patent ID: 7031558

Claim:
A device, comprising: an input bonding pad and an output bonding pad each having a respective length less than one-quarter of a target wavelength corresponding to a target operating frequency, a respective characteristic impedance less than a target source impedance, and a respective reactive impedance that is capacitive up to at least the target operating frequency; an input microstrip line and an output microstrip line each having a respective length less than one-quarter of the target wavelength, a respective characteristic impedance greater than the target source impedance, and a respective reactive impedance that is inductive up to at least the target operating frequency; and an electro-absorption modulator having a signal electrode with a length less than one-quarter of the target wavelength, a characteristic impedance less than the target source impedance, and an equivalent circuit of a shunt capacitor at the target operating frequency; wherein the input microstrip line is connected between the input bonding pad and the electro-absorption modulator, the output microstrip line is connected between the output bonding pad and the electro-absorption modulator, and the input bonding pad, the output bonding pad, the input microstrip line, the output microstrip line, and the electro-absorption modulator have an equivalent circuit of a distributed low-pass filter transmission line circuit having a characteristic impedance matching the target source impedance at the target operating frequency.