>1-Tb/s on-board optical engine for high-density optical interconnects

We demonstrate a >1-Tb/s VCSEL-based on-board optical engine for high-density optical interconnects. The optical engine integrates 28-Gb/s × 24-channel transmitter and receiver into one package of 1-inch² footprint. Hence, the total data rate is as high as 1.34 Tb/s. The thermal simulation is performed when operating all 24 channels with the total power of 9.1 W with CDR and 6.0 W without CDR, assuming an actual air-cooling environment. The optical engine can perform within the operating case temperature range at an ambient temperature of 40 °C and exhibit a good signal quality in a parallel loop-back link.

1. Introduction

On-board optical engines have been expected to realize a high data rate density in the next generation optical interconnects. So far, -channel transceiver on-board optical engines have been demonstrated with the total data rate of 0.6 Tb/s with a footprint of 1 inch² [1]–[4]. To move on the next generation 400 Gigabit Ethernet and a higher data rate protocol, a higher-density on-board optical engine demanded. We demonstrated - channel vertical cavity surface emitting laser (VCSEL)-based transceiver optical engine with 1-inch² footprint [5]. The optical engine employs 28-Gb/s VCSEL/photodiode (PD) arrays and CDR-integrated VCSEL driver (VD)/trams-impedance amplifier (TIA). Subsequently, the total data rate was as high as 1.34 Tb/s. The total power consumption was as high as 9.1 W when operating all 24 channels simultaneously. The unique packaging structure enables using the whole area of the top surface for thermal dissipation [6]. To study an actual usage in an air cooling environment in a rack, we perform thermal simulations for the optical engine mounted on a land grid array (LGA). We derive the operating case temperature when operating all 24 channels under the condition of activating and bypassing the clock data recovery (CDR) functionality. We also evaluate the signal quality in a loop-back link under the test conditions.