Chinese Optics Letters, 2019, Vol. 17, Issue 12, pp.
Package-level passive equalization technology enabling DML-based 112 Gb/s/λ PAM4 transmission
Zhang Zhike, Li Jinye, Zhao Zeping, Liu Jianguo, Wang Xingjun
- Institute of Semiconductors, Chinese Academy of Sciences, Beijing
We demonstrate a package-level passive equalization technology in which the wire bonding-induced resonance effect is used to compensate for the limited gain strength within the Nyquist frequency. The corresponding gain strength under various inductance and capacitance combinations could be quantitatively determined using a numerical simulation. With the increase in the Nyquist frequency, the capacitance shows a greater effect on the gain strength than the inductance. Therefore, the parasitic capacitance should be decreased to realize the desired gain strength at a higher Nyquist frequency. With this equalization technology, a gain strength of 5.8 dB is obtained at 22 GHz, which can compensate for the limited bandwidth for the 112 Gbps PAM4 signal. The experimental results show that 112Gb/s/λ PAM4 transmission based on a directly modulated laser module can be realized with a bit error rate of 1 × 10−3 at a received optical power of 3 dBm.