Jun 9 – 15, 2018
Woodlands Conference Center
America/New_York timezone
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A 14 Gbps low power VCSEL driver for high-energy physics experiments

Jun 14, 2018, 2:35 PM
1h 30m
Woodlands Conference Center

Woodlands Conference Center

159 Visitor Center Dr, Williamsburg, VA 23185
Poster presentation Front End Electronics and Fast Digitizers Poster 2


Wei Zhou (Central China Normal University)


We present the design and the preliminary test results of a dual-channel VCSEL-driver ASIC, LOCld65 with the aim of introducing it for the upgrade of the front-end readout system of the ATLAS Liquid Argon Calorimeter. LOCld65 is fabricated in a commercial 65-nm CMOS process, and each channel operates up to 14 Gbps. LOCld65 provides a perfect match to lpGBT, which is a single-channel 10 Gbps serializer-deserializer ASIC developed chiefly for HL-LHC upgrades. Each channel of LOCld65 can be turned off individually thus providing a flexible solution on the front-end module design. LOCld65 can also be used for general optical transmission applications in high-energy physics experiments.

The analog core of LOCld65 consists of a continuous-time equalizer, a four-stage limiting amplifier, and a high-current differential driver. The programmable equalizer can effectively mitigate the high-frequency loss due to the traces on the printed circuit board. A shared inductive-peaking technique is adopted to extend the bandwidth and reduce the chip area. A programmable active feedback circuit is used to optimize the gain and bandwidth in different process corners. The two-channel design is fabricated on a 1 mm x 1 mm die area and packaged in a 24-pin QFN package.

We have preliminary eye mask test results for LOCld65. It passed at 10-Gbps and 14-Gbps with an 850-nm 10-Gpbs VCSEL. The power dissipation of each channel is 58 mW with a 6-mA modulation current and a 2-mA bias current. We plan to test the radiation effects, including SEE and TID in the future.

Institute Central China Universtiy
Description 14Gbps ASIC
Minioral Yes
Speaker Wei Zhou
Country China

Primary author

Wei Zhou (Central China Normal University)


Prof. Xiangming Sun (Central China Normal University CCNU (CN)) Le Xiao (Central China Normal University) Dr Di Guo (Central China Normal University) Quan Sun (Southern Methodist University) Datao Gong (Southern Methodist Univeristy) Tiankuan Liu (Southern Methodist University (US)) Chonghan Liu (Southern Methodist University) Guangming Huang (Central China Normal University (CCNU)) Jingbo Ye (Southern Methodist University, Department of Physics)

Presentation materials