Research On Silicon-based Optoelectronic Mz Modulator Driver For High Speed Cmmunication

With the advent of the 5G era,the exchange of global data traffic is growing,and people are eager for the transmission systems which have high speed and large capacity.Therefore,the optical communication systems are widely used due to their advantages of high bandwidth,large capacity and low attenuation.As an important part of the transmitter in the optical communication system,the performance of the driver determines the communication quality of the entire optical communication system.Based on the application requirements of the next generation 400Gb/s communication system,a high-speed and large-swing driver for Mach-Zehnder(MZ)modulator is designed.Through analyzing the working principle of the optical communication system and combining with the practical application,the specific method of the MZ modulator driver is presented.The high-speed driving circuit is the core of this design,which mainly includes the continuous time linear equalizer,the variable gain amplifier,the pre-driver and the output driver.The equalizer uses on-chip inductors to provide peak frequency.The variable gain amplifier uses shunt-peaking technology,negative feedback technology,and capacitor neutralization technology to extend the bandwidth and improve the linearity of the circuit.Based on push-pull topology structure,the output driver is improved to achieve high-speed and large-swing output.Finally,using the continuous time negative feedback of the DC offset calibration circuit,the offset voltage is neutralized in the system.Under the Global Foundry 130nm SiGe BiCMOS8XP process,the circuit design and layout design of the driver were completed.And then,the post-simulation verification is implemented.The simulation results show that the equalizer can compensate the channel loss of 4dB-19dB,and the variable gain amplifier can adjust the gain of 11dB-16dB continuously.Above all,the-3dB bandwidth of the driver is 33.78GHz and the gain is 26.5dB.The differential output swing achieves 4Vpp when the amplitude of PAM4 input signal is 0.2Vpp and the rate is 50GBaud(100Gb/s).The power consumption of the chip is 796mW,and the area is 1400?m×1400?m.