Receiver optical assemblies (roas) having photo-detector remotely located from transimpedance amplifier, and related components, circuits, and methods

A method of assembly of a receiver optical assembly (ROA), comprising:

• disposing a photo-detector in an optical header packaging on a printed circuit board (PCB), the photo-detector configured to detect and convert input optical signals into output electrical signals;
• disposing a complementary metal oxide semiconductor (CMOS)-based differential transimpedance amplifier (TIA) circuit provided in an integrated circuit on the PCB remotely located from the optical header packaging, the CMOS-based differential TIA circuit comprising a first differential input node and a second differential input node, and the CMOS-based differential TIA circuit having a TIA input impedance of at least ten (10) ohms to reduce a ringing effect over the first differential input node and the second differential input node;
• disposing a transmission circuit in the PCB comprised of disposing a first transmission line as a first PCB trace in the PCB and a second transmission line as a second PCB trace in the PCB;
• coupling the first differential input node of the CMOS-based differential TIA circuit to the first transmission line and coupling the second differential input node of the CMOS-based differential TIA circuit to the second transmission line;
• and
• coupling a first node of the photo-detector to the first transmission line and coupling a second node of the photo-detector to the second transmission line to couple the photo-detector to the CMOS-based differential TIA circuit to amplify the output electrical signals received from the photo-detector.

A receiver optical assembly (ROA), comprising:

• a photo-detector disposed in an optical header packaging, the photo-detector configured to detect and convert input optical signals into output electrical signals;
• a complementary metal oxide semiconductor (CMOS)-based differential transimpedance amplifier (TIA) circuit comprising:
• a first CMOS-based TIA having a first differential input node and a first output node;
• a second CMOS-based TIA having a second differential input node and a second output node;
• and
• an output CMOS-based differential amplifier having a first differential input node coupled to the first output node of the first CMOS-based TIA, and a second differential input node coupled to the second output node of the second CMOS-based TIA, the output CMOS-based differential amplifier configured to reject common noise amplified by the first CMOS-based TIA and the second CMOS-based TIA;
• the CMOS-based differential TIA circuit having a TIA input impedance of at least ten (10) ohms to reduce a ringing effect over the first differential input node and the second differential input node;
• and
• a transmission circuit comprised of a first transmission line coupled to the first differential input node of the first CMOS-based TIA, and a second transmission line coupled to the second differential input node of the second CMOS-based TIA;
• and
• a first node of the photo-detector coupled to the first transmission line and a second node of the photo-detector coupled to the second transmission line to couple the photo-detector to the CMOS-based differential TIA circuit to amplify the output electrical signals received from the photo-detector.