Equalizer Circuit [Circuit Intuitions]

In a previous article [ibid., vol. 11, no. 3, pp. 7–9, 2019. doi: 10.1109/MSSC.2019.2922885] in this series, we discussed how a piece of wire connecting a data transmitter to a receiver attenuates the transmit signal at high frequencies, making the task of reliable data recovery by the receiver difficult. To compensate for the channel attenuation, we design an equalizer circuit and place it after the channel. The equalizer circuit has a transfer function that is the inverse of the wire’s transfer function in the frequency range of interest. The equalizer is designed such that the combined transfer function of the wire and the equalizer circuit will be flat up to the Nyquist frequency, defined as half of the baud rate. In this article, we review a common equalizer known as the continuous-time linear equalizer. We rely on the techniques described in the first article in this series [ibid., vol. 6, no. 2, pp. 8–10, 2014. doi: 10.1109/MSSC.2014.2315062] to find the transfer function of this equalizer