Compact TO-CAN Header With Bandwidth Excess 40 GHz

A large bandwidth transistor outline (TO)-CAN header used in a low cost laser module was designed through a three dimensional full wave electromagnetic simulation and demonstrated by a direct measurement technique. The simulation results show that the proposed TO-CAN header provides a resonance-free transmission bandwidth in excess of 40 GHz with a reflection loss of 25 GHz under -10 dB with an ideal 50 Ω terminal. A pair of specially designed K type adaptors was used to accommodate the TO-CAN header for the high frequency measurements. This is a direct contact setup, without extra parasitic effects, and allowing a near resonance-free measurement. The experimental results are in good agreement with simulated results in the frequency range up to 40 GHz. A time-domain reflectometry measurement and a 40 Gbit/s eye diagram test were made to verify the performance. In addition, a laser module packaged with the TO-CAN header is proposed. By taking the bonding wires into account, the simulated transmission bandwidth of the module is over 35 GHz and a clear 25 Gbit/s eye diagram is obtained. This cost effective package solution of laser module can be applied in the next generation 100 Gigabit Ethernet (100 GbE) network.