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In this paper, the design and layout of a 2.5 Gbps arrayed VCSEL driver for optical transceiver having arrayed multi-channel of integrating module is confirmed. In this paper, a 4 channel 2.5 Gbps VCSEL (vertical cavity surface emitting laser) driver array with automatic optical power control is implemented using 0.18 μm CMOS process technology that drives a 1550 μm high speed VCSEL used in optical transceiver. To enhance the bandwidth of the optical transmitter, active feedback amplifier with negative capacitance compensation is exploited. We report a distinct improvement in bandwidth, voltage gain and operation stability at 2.5Gbps data rate in comparison with existing topology. The 4-CH chip consumes only 140 mW of DC power at a single 1.8V supply under the maximum modulation and bias currents, and occupies the die area of 850 μm × 1,690 μm excluding bonding pads.

Sung-Chan Cho et al. 109 We propose a novel very short (< 300 µm) vertical directional coupler switch with high extinction ratios larger than 30 dB. The device consists of a switching operation induced section (SOIS), an extinction ratio adjusted section (ERAS), and an extinction ratio enhanced section (ERES). These are achieved by changing the refractive index of one core. The switching operation is induced by changing the refractive index of one core in the SOIS. The improvement of extinction ratios larger than 30 dB for both the cross and bar states is made by controlling the asymmetry of the refractive indices of both cores in the ERES. Through the ERAS, different extinction ratios between the cross and bar states at the end of the SOIS are changed to the same value. For this reason, the optimum asymmetry of the refractive indices of the cores for the maximum extinction ratios and the lengths of ERES are the same for cross and bar states. Design guidelines for high extinction ratios with large tolerances are presented.

We propose a novel driver circuit design using 0.18μm CMOS process technology that drives a 1550 nm high-speed VCSEL used in optical transceiver. We report a distinct improvement in bandwidth, voltage gain and eye diagram at 3.1Gb/s data rate in comparison with existing topology. In this paper, the design and layout of a 3.1Gb/s VCSEL driver for optical transceiver having arrayed multi-channel of integrating module is confirmed.

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