Wide-band integrated optical receiver with improved dynamic range using a current switch at the input

The front end of optical transmission systems usually consists of a low-noise, wide-band, negative-feedback transimpedance or current amplifier. The dynamic range of current amplifiers can be extended considerably by passing large input currents directly to the output of the amplifier. It is shown that the required current switch does not deteriorate the sensitivity of the receiver. A complete front end, using an external p-i-n photodiode, is integrated in a 2.5-GHz bipolar technology. The receiver has a dynamic range (DR) of 73 dB in a bandwidth of 220 MHz and consumes a supply current of 1.5 mA.<
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