The present invention discloses a novel high-speed optocoupler
integrated circuit, which is cascaded in sequence by a current bias circuit, a transimpedance circuit, a
comparator circuit, and a shaping buffer circuit; the transimpedance circuit adopts a current
multiplexing controllable
common source and
common gate transimpedance, including two parts that are symmetrical up and down, each part including: a transimpedance bias circuit, a transimpedance
negative feedback, and a
capacitor, the input stage of the transimpedance circuit is connected with the current bias circuit and the transimpedance
negative feedback, and an AC
coupling capacitor is connected between the mirror current circuit and the input stage; the
comparator circuit includes: a bias circuit, an
amplifier circuit, an
active load is connected in series at the input stage of the
comparator circuit, and the input end is connected with the
amplifier circuit; the shaping circuit is composed of a two-stage
inverter. The present invention applies the current
multiplexing method to the RGC
transimpedance amplifier, improves the
mutual impedance performance and obtains higher responsiveness and overall
system conversion gain, while achieving the same
system bandwidth.