GX39220 - 2x96Gbaud Linear TIA for Coherent Optics | Renesas
MPN: GX39220 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $121.2 | $121.20 |
| 10 | $110.5 | $1,105.00 |
| 100 | $96 | $9,600.00 |
| 500 | $84 | $42,000.00 |
| 1,000 | $75 | $75,000.00 |
GX39220 Overview
A Linear TIA is a high-speed amplifier that converts the small differential photocurrent produced by a coherent photodetector (typically a 90-degree optical hybrid followed by balanced photodiodes) into a differential voltage with sufficient bandwidth and linearity for downstream high-speed ADC sampling. In coherent optical transceivers, the TIA sits at the analog front-end between the optical detector and the DSP/ADC, and its bandwidth, noise, and linearity directly limit the achievable OSNR and the symbol rate of the recovered constellation. The GX39220 is therefore a member of the optical front-end IC family within Renesas' coherent optics portfolio.
Key features include two independent linear TIA channels with bandwidth sufficient for 96 Gbaud PAM/QAM symbol rates, integrated automatic gain control to extend dynamic range across strong and weak optical signals, low noise performance suitable for high-order QAM constellations, and a low-power architecture tailored to dense pluggable modules. The differential output is designed to drive high-speed ADCs directly over short controlled-impedance traces.
Typical applications include 400G/800G/1.6T coherent pluggable transceivers (CFP2, CFP4, QSFP-DD/OSFP variants with coherent DSPs), DWDM line-side coherent optics in metro and long-haul transport, and high-speed coherent LiDAR front-end prototypes. Pair the GX39220 with a coherent DSP such as Renesas' R-series CR series and a high-speed ADC for a complete coherent receiver analog front-end. When designing with the part, follow high-speed PCB practices - controlled-impedance differential routing, low-loop-area decoupling, and short bond-wire transitions from the photodiode to the TIA input - to preserve the bandwidth and noise floor quoted in the Renesas datasheet.
Drop-in alternatives for GX39220 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with GX39220 (same form factor and footprint) — differing in Mounting Type, Number of Channels.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
GX32220
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
GX39220-DNT
✅ Drop-In✓ In Stock
$121.2 / Unit
View Datasheet →GX39220 Maximum Ratings & Electrical Characteristics
| Product Type | Linear Transimpedance Amplifier (TIA) |
| Number of Channels | 2 (I and Q) |
| Symbol Rate | 96 Gbaud per channel |
| Application | Coherent optical receivers, 400G/800G/1.6T pluggable modules |
| Module Form-Factor | CFP2, CFP4 |
| Output Interface | Differential (per channel) |
| Technology | Silicon high-speed analog process |
| Mounting Type | Surface Mount |
GX39220 standard Pin Configuration Guide
Pin configuration for GX39220 (standard package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for GX39220.
Refer to the datasheet for full pin configuration.
Typical Applications
GX39220 is suitable for 6 applications: 400G/800G Coherent Pluggable Transceivers, DWDM Long-Haul and Metro Line-Side Optics, 1.6T Coherent Optical Modules, Coherent Optical Receiver Evaluation Boards, Data Center Interconnect (DCI) Coherent Links, High-Speed Coherent LiDAR and Sensing Front-Ends.
400G/800G Coherent Pluggable Transceivers
The Renesas GX39220 is well-suited to 400G and 800G coherent pluggable transceivers (CFP2, CFP4, QSFP-DD coherent, OSFP coherent) because it integrates two linear TIA channels sized for the I and Q arms of a coherent optical front-end at 96 Gbaud per channel. Its dual-channel integration halves the analog-IC bill-of-materials and shortens bond-wire lengths from balanced photodiodes to the TIA inputs - critical for preserving the noise and bandwidth required by 16-QAM or 64-QAM constellations. At 96 Gbaud per polarization, a dual-polarization link built around the GX39220 can deliver 800 Gb/s per wavelength when paired with a suitable coherent DSP. Designers should follow the Renesas datasheet's PCB layout guidance and use controlled-impedance differential routing to preserve the small-signal bandwidth.
Recommended
DWDM Long-Haul and Metro Line-Side Optics
For DWDM line-side coherent optics in metro and long-haul transport, the GX39220's linear TIA architecture preserves the amplitude and phase information required to recover high-order QAM constellations over thousands of kilometers of single-mode fiber. The two-channel I/Q integration matches the natural output of a 90-degree optical hybrid + balanced photodetector front-end, eliminating the need for separate I and Q TIAs and reducing board area. At 96 Gbaud, the part supports flexible-grid line-side capacities including 400G and 800G per wavelength with margin for soft-decision FEC. Ensure input-referred noise and bandwidth targets are verified against the Renesas datasheet when sizing OSNR budgets.
Recommended
1.6T Coherent Optical Modules
The 96 Gbaud per-channel capability of the GX39220 makes it a candidate front-end TIA for emerging 1.6T coherent optical modules that aggregate multiple 800G wavelengths or use single-carrier 200 GBd architectures. Its low-power, dual-channel integration enables dense channel packing within small-form-factor modules where thermal headroom is limited. Designers building 1.6T prototypes should pair the GX39220 with the latest 5nm coherent DSPs (Renesas' CR-series or equivalent) and verify inter-symbol interference and crosstalk budgets against the Renesas datasheet. The differential output is sized to drive directly into high-speed ADCs over short controlled-impedance traces.
Recommended
Coherent Optical Receiver Evaluation Boards
The GX39220-DNT is commonly used as the analog front-end of coherent optical receiver evaluation boards and reference designs from Renesas and its partners, enabling lab characterization of coherent link performance at 96 Gbaud per channel. The integrated dual-channel TIA simplifies evaluation board layout by reducing component count and allowing direct connection from a packaged coherent receiver optical subassembly (ROSA) to the evaluation PCB. Typical eval-board designs combine the GX39220 with a Renesas coherent DSP, FPGA-based DSP development kit, and tunable laser source to demonstrate constellation recovery and OSNR sensitivity across modulation formats.
Recommended
Data Center Interconnect (DCI) Coherent Links
For data center interconnect (DCI) coherent links spanning metro distances up to ~120 km, the GX39220's linear TIA performance supports the high-order QAM constellations needed to maximize capacity per wavelength on DCI links. Pairing two GX39220s (one per polarization) with a coherent DSP enables 400G/800G coherent modules in QSFP-DD or OSFP form factors, the dominant DCI pluggable formats. Its compact dual-channel integration helps meet the strict power and thermal budgets of QSFP-DD coherent modules. Verify OSNR and fiber-nonlinearity margins against the Renesas datasheet when planning the optical link budget.
Recommended
High-Speed Coherent LiDAR and Sensing Front-Ends
Beyond telecom, the GX39220's 96 Gbaud dual-channel linear TIA architecture can serve as a high-bandwidth front-end in coherent FMCW LiDAR and other high-speed optical sensing applications where preservation of amplitude and phase across a wide modulation bandwidth is essential. The two-channel I/Q architecture maps naturally to coherent LIDAR mixing where both in-phase and quadrature beat signals must be captured simultaneously. Designers should evaluate noise figure, bandwidth, and linearity against sensing-range requirements; consult the Renesas datasheet for absolute maximum ratings and confirm the part is qualified for the target operating environment.
Recommended
Recommended Products Summary
Engineering reference data for GX39220 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | GX32220 | GX39220-DNT |
|---|---|---|---|
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Number of TIA Channels | 2 (I and Q) | 2 (I and Q) | 2 (I and Q) |
| Architecture | Linear (coherent) | Linear (coherent) | Linear (coherent) |
| Target Module Form Factor | CFP2 / CFP4 | CFP2 / CFP4 | CFP2 / CFP4 |
| Output Interface | Differential | Differential | Differential |
Key Differentiators
- Dual-channel I/Q integration at 96 Gbaud (vs Single-channel coherent TIAs)
- CFP2/CFP4 form-factor optimized (vs Discrete dual-channel TIA boards)
- Linear (not limiting) architecture preserves constellation (vs Limiting TIAs (NRZ/PAM4))
Design Notes
The GX39220 is a 96 Gbaud analog device; controlled-impedance (typically 100 ohm differential) PCB routing from the photodiode inputs to the TIA and from the TIA outputs to the ADC inputs is essential. Keep input and output routes on separate layers with continuous reference planes, and minimize bond-wire lengths from the photodiode ROSA to the TIA input - long bond wires create resonances that degrade the small-signal bandwidth. Use the manufacturer land-pattern file from the Renesas datasheet when generating gerbers.
Estimated: a 2-channel 96 Gbaud linear TIA in a coherent optical front-end typically dissipates 0.5-1.5 W total depending on supply voltage and channel configuration. Provide low-impedance decoupling with multiple capacitor values (e.g., 100 nF, 10 nF, 1 nF) placed as close as possible to each supply pin, and use a dedicated analog supply plane to isolate switching noise from the TIA. Confirm exact power dissipation against the Renesas datasheet once published.
The GX39220 outputs are designed to drive high-speed ADCs directly. Match trace lengths within each differential pair to within 5 mils and use series AC-coupling capacitors near the ADC inputs. Keep the TIA outputs away from any high-current digital traces to avoid coupling switching noise into the analog signal path. For coherent applications, I/Q channel-to-channel skew must be minimized to preserve constellation rotation accuracy.
Do not substitute a limiting TIA for the GX39220 in a coherent design - a limiting TIA saturates the analog amplitude and destroys constellation information. Do not assume the GX39220's pinout from a generic photo - always use the Renesas datasheet pinout and land pattern. Finally, when migrating between GX-series variants, verify baud rate, channel count, supply voltage, and pinout against the specific datasheet before committing to PCB layout.
Compliance Information
Compliance information not present in the verified web data; consult the Renesas datasheet for explicit RoHS/REACH/lead-free status. AEC-Q100 not applicable for telecom coherent TIAs.
