Switch assembly

An application specific integrated circuit (ASIC) layer for use in a vertically-stacked multi-layer switch assembly comprising a substrate, a photonic integrated circuit (PIC) layer stacked on the substrate, and the ASIC layer stacked on the PIC layer, the ASIC layer comprising:

• a two-dimensional array of modulator drivers comprising rows of modulator drivers and columns of modulator drivers;
• and
• a two-dimensional array of transimpedance amplifiers comprising rows of transimpedance amplifiers and columns of transimpedance amplifiers,
• wherein, the two-dimensional array of modulator drivers and the two-dimensional array of transimpedance amplifiers comprise an arrangement in the ASIC layer in which rows of modulator drivers alternate with rows of transimpedance amplifiers, or columns of modulator drivers alternate with columns of transimpedance amplifiers,
• wherein, the PIC layer comprises a two-dimensional array of modulators and a two-dimensional array of photodiodes, in which the two-dimensional array of modulators and the two-dimensional array of photodiodes comprise an arrangement in the PIC layer in which rows of modulators alternate with rows of photodiodes, or columns of modulators alternate with columns of photodiodes,
• wherein, the arrangement in the ASIC layer, comprising the two-dimensional array of modulator drivers and the two-dimensional array of transimpedance amplifiers, mirrors the arrangement in the PIC layer, comprising the two-dimensional array of modulators and the two-dimensional array of photodiodes, such that each modulator driver in the ASIC layer corresponds to a modulator in the mirrored PIC layer and each transimpedance amplifier in the ASIC layer corresponds to a photodiode in the mirrored PIC layer, and
• wherein, upon the ASIC layer and the PIC layer being stacked in the vertically-stacked multi-layer switch assembly, the arrangement in the ASIC layer, comprising the two-dimensional array of modulator drivers and the two-dimensional array of transimpedance amplifiers, is aligned with the arrangement in the PIC layer comprising, the two-dimensional array of modulators and the two-dimensional array of photodiodes, such that each modulator driver in the ASIC layer is electrically connected with, and configured to drive, its corresponding modulator in the mirrored arrangement in the PIC layer, and each transimpedance amplifier is electrically connected with, and configured to amplify a signal from, its corresponding photodiode in the mirrored arrangement in the PIC layer.