| 摘要 |
A serial photonic digital-to-analog converter employs a heterojunction thyristor device configured for optically-controlled sampling/switching to convert a digital word encoded by a serial digital optical data signal (e.g., serial optical bit stream) into a corresponding analog electrical signal. A voltage reference is operably coupled to the electrical input terminal of the heterojunction thyristor device. The voltage reference cooperates with the heterojunction thyristor device to sequentially generate at its electrical output terminal a voltage signal representing contribution of each bit of the digital word encoded in the serial digital optical data signal. A summing network is operably coupled to the electrical output terminal of the device. The summing network sequentially sums contribution of the voltage signal over the sequence of bits to produce an analog electrical signal corresponding to the digital word for output therefrom. Preferably, the summing network includes an adding node, sample and hold circuit, and a feedback path between the sample and hold circuit and the adding node. In addition, the voltage reference preferably supplies a voltage level corresponding to the maximum voltage level of the analog electrical signal divided by 2<(N-1)>, where N is the number of bits in said digital word, and the feedback path comprises an amplifier that amplifies output of the sample and hold circuit by a factor of 2.
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