A comprehensive Verilog-A VCSEL model for >20Gb/s optical interconnect transceiver circuit design

Directly-modulated vertical-cavity surface-emitting lasers (VCSELs) are commonly used in short-reach optical interconnect applications. In order to enable efficient optical interconnect transceiver systems operating at data rates in excess of 20Gb/s, cosimulation environments which allow for the optimization of driver circuitry with accurate compact VCSEL models are necessary. This paper presents a compact comprehensive Verilog-A VCSEL model which captures thermally-dependent electrical and optical dynamics and provides dc, small signal, and large-signal simulation capabilities. The device’s electrical behavior is described with an equivalent circuit which captures both large-signal operation and electrical parasitics, while the optical response is captured with a rate-equation-based model, with bias and temperature dependencies incorporated into key electrical and optical model parameters. Experimental verification of the model is performed at 25Gb/s with a 990nm VCSEL to study the impact of bias current level and substrate temperature. External Posting Date: February 10, 2016 [Fulltext] Internal Posting Date: February 10, 2016 [Fulltext] Approved for External Publication  Copyright 2016 Hewlett Packard Enterprise Development LP A comprehensive Verilog-A VCSEL model for >20Gb/s optical interconnect transceiver circuit design Binhao Wang,1, 2, * Wayne Sorin,2 Samuel Palermo,1 and Michael Tan2 1Department of Electrical & Computer Engineering, Texas A&M University, College Station, CA 77843, USA 2Hewlett Packard Labs, Hewlett Packard Enterprise, Palo Alto, CA 94304, USA *[email protected] Abstract: Directly-modulated vertical-cavity surface-emitting lasers (VCSELs) are commonly used in short-reach optical interconnect applications. In order to enable efficient optical interconnect transceiver systems operating at data rates in excess of 20Gb/s, co-simulation environments which allow for the optimization of driver circuitry with accurate compact VCSEL models are necessary. This paper presents a compact comprehensive Verilog-A VCSEL model which captures thermally-dependent electrical and optical dynamics and provides dc, small signal, and large-signal simulation capabilities. The device’s electrical behavior is described with an equivalent circuit which captures both largesignal operation and electrical parasitics, while the optical response is captured with a rate-equation-based model, with bias and temperature dependencies incorporated into key electrical and optical model parameters. Experimental verification of the model is performed at 25Gb/s with a 990nm VCSEL to study the impact of bias current level and substrate temperature. 2015 Optical Society of America OCIS codes: (250.7260) Vertical cavity surface emitting lasers; (230.2090) Electro-optical devices; (250.5300) Photonic integrated circuits; (200.4650) Optical interconnects. Directly-modulated vertical-cavity surface-emitting lasers (VCSELs) are commonly used in short-reach optical interconnect applications. In order to enable efficient optical interconnect transceiver systems operating at data rates in excess of 20Gb/s, co-simulation environments which allow for the optimization of driver circuitry with accurate compact VCSEL models are necessary. This paper presents a compact comprehensive Verilog-A VCSEL model which captures thermally-dependent electrical and optical dynamics and provides dc, small signal, and large-signal simulation capabilities. The device’s electrical behavior is described with an equivalent circuit which captures both largesignal operation and electrical parasitics, while the optical response is captured with a rate-equation-based model, with bias and temperature dependencies incorporated into key electrical and optical model parameters. Experimental verification of the model is performed at 25Gb/s with a 990nm VCSEL to study the impact of bias current level and substrate temperature. 2015 Optical Society of America OCIS codes: (250.7260) Vertical cavity surface emitting lasers; (230.2090) Electro-optical devices; (250.5300) Photonic integrated circuits; (200.4650) Optical interconnects. References and links 1. C. Kachris, K. Kanonakis, and I. Tomkos, "Optical interconnection networks in data centers: recent trends and future challenges," IEEE Comm. Mag. 51(9), 39-45 (2013). 2. C. Minkenberg, "HPC networks: challenges and the role of optics," in OSA Optical Fiber Communication Conference, W3D3 (2015). 3. 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