Switch assembly
An integrated switch assembly having a stacked configuration, the integrated switch assembly comprising: a first layer, the first layer comprising a photonic integrated circuit, PIC; a second layer, the second layer comprising a switch ASIC; wherein the first layer is mounted onto a substrate and the second layer is mounted on top of the first layer.
1 . 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.
2 . The ASIC layer of claim 1 , wherein the ASIC layer and the PIC layer are aligned to minimize a length of an electrical connection between each modulator driver in the ASIC layer and the corresponding modulator in the PIC layer, and to minimize a length of an electrical connection between each transimpedance amplifier in the ASIC layer and the corresponding photodiode in the PIC layer.
3 . The ASIC layer of claim 1 , wherein the electrical connection between each modulator driver of the ASIC layer and the corresponding modulator of the PIC layer comprises a copper pillar or a solder bump.
4 . The ASIC layer of claim 1 , wherein the electrical connection between each transimpedance amplifier of the ASIC layer and the corresponding photodiode of the PIC layer comprises a copper pillar or a solder bump.
5 . The ASIC layer of claim 1 , wherein the PIC layer further comprises one or more data input points at which optical fibres are connected to bring optical signals into components in the PIC layer.
6 . The ASIC layer of claim 5 , wherein the one or more data input points include an optical demultiplexer.
7 . The ASIC layer of claim 1 , wherein the PIC layer further comprises one or more data output points at which optical fibres are connected to take out optical signals from components in the PIC layer.
8 . The ASIC layer of claim 7 , wherein the one or more data output points include an optical multiplexer.
9 . The ASIC layer of claim 1 , wherein the PIC layer further comprises one or more banks of lasers.
10 . The ASIC layer of claim 9 , wherein the one or more banks of lasers comprise hybrid lasers disposed around a perimeter of the PIC layer.
11 . The ASIC layer of claim 1 , wherein the PIC layer further comprises power splitters, multiplexers, and demultiplexers disposed around a perimeter of the PIC layer, and wherein the two-dimensional arrays of modulators and photodiodes are disposed in a central region of the PIC layer.
12 . The ASIC layer of claim 1 , wherein the PIC layer further comprises at least one serializer/deserializer (SerDes).