LightRail LPO 1.6T
About the LightRail LPO 1.6T PCB
LightRail LPO 1.6T is an open source PCB design by lightrail-dev, published on GitHub. It is a 32-layer board measuring 420 × 355 mm, with 2766 components from 23 distinct parts.
Other key parts include the NCE_BGA2500_HBM4, TFLN_PIC_8CH_200G, ISL99390, XCKU5P and ISL69260. By type, the board carries 2360 capacitors, 80 resistors, 73 ICs, 67 connectors and 48 inductors.
From the project
Project: LightRail AI Compute Node (Dual-CPO, NCE + HBM4 co-packaged, 1.6 Tbps photonic I/O) Model: LR-P3A Revision: 6.3 (32-layer HDI, IPC-6012 Class 3, 1000 A PDN — fully routed) Date: 2026-05-18 Company: LightRail AI
Project: LightRail AI Compute Node (Dual-CPO, NCE + HBM4 co-packaged, 1.6 Tbps photonic I/O) Model: LR-P3A Revision: 6.3 (32-layer HDI, IPC-6012 Class 3, 1000 A PDN — fully routed) Date: 2026-05-18 Company: LightRail AI
See docs/Architecture.md for the block diagram and signal-flow description.
See docs/Stackup.md for the impedance target for each net class against the assumed dielectric stackup.
Main components on the LightRail LPO 1.6T
LightRail LPO 1.6T bill of materials (BOM)
2766 components, 23 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 2 | NCE_BGA2500_HBM4 | NCE_BGA2500_40x40mm | U101, U201 |
| 2 | TFLN_PIC_8CH_200G | TFLN_PIC_17x17mm | U102, U202 |
| 48 | ISL99390 | DrMOS_PowerPAK_8x8mm | U302, U303, U304, U305, U306, U307, U308, U309 +40 |
| 2 | XCKU5P | BGA-676_FPGA | U401, U402 |
| 4 | ISL69260 | QFN-48 | U403, U404, U405, U406 |
| 2 | AD9082 | QFN-64_DAC | U411, U412 |
| 8 | HMC7044 | QFN-32_RF | U421, U422, U423, U424, U425, U426, U427, U428 |
| 2 | SNSPD_8CH | LGA-16_SNSPD | U431, U432 |
| 2 | QMEM_CELL | LGA-24_QMEM | U441, U442 |
| 1 | CXL_SWITCH | BGA-256_CXL | U450 |
| 1 | PCIe_Gen6_x16_CEM | PCIe_CEM_x16_164pin | J1 |
| 2 | 12VHPWR_600W | 12VHPWR_Molex_203713 | J2, J3 |
| 64 | QSFP-DD | QSFP_DD_Cage | J10, J11, J12, J13, J14, J15, J16, J17 +56 |
| 12 | 100uF_10V | C_Tantalum_3528 | C_U0_T1_0, C_U0_T1_1, C_U0_T1_2, C_U0_T1_3, C_U0_T1_4, C_U0_T1_5, C_U1_T1_0, C_U1_T1_1 +4 |
| 18 | 10uF | C_0805 | C_U0_T2_0, C_U0_T2_1, C_U0_T2_2, C_U0_T2_3, C_U0_T2_4, C_U0_T2_5, C_U0_T2_6, C_U0_T2_7 +10 |
| 36 | 1uF | C_0402 | C_U0_T3_0, C_U0_T3_1, C_U0_T3_2, C_U0_T3_3, C_U0_T3_4, C_U0_T3_5, C_U0_T3_6, C_U0_T3_7 +28 |
| 72 | 100nF | C_01005 | C_U0_T4_0, C_U0_T4_1, C_U0_T4_2, C_U0_T4_3, C_U0_T4_4, C_U0_T4_5, C_U0_T4_6, C_U0_T4_7 +64 |
| 48 | 1.6x0.8 | FB_passive | FB663, FB664, FB665, FB666, FB667, FB668, FB669, FB670 +40 |
| 558 | 1.0x0.5 | C_passive | C1, C2, C3, C4, C5, C6, C7, C8 +550 |
| 96 | 2.0x1.25 | C_passive | C487, C488, C489, C490, C491, C492, C493, C494 +88 |
Show 3 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 32 | 3.2x1.6 | C_passive | C711, C712, C713, C714, C715, C716, C717, C718 +24 |
| 1674 | 0.6x0.3 | C_passive | C815, C816, C817, C818, C819, C820, C821, C822 +1666 |
| 80 | 1.0x0.5 | R_passive | R583, R584, R585, R586, R587, R588, R589, R590 +72 |
LightRail LPO 1.6T design files
The KiCad project lives in the lightrail-dev/new repository on GitHub; these links point at the commit this page was built from.
LightRail LPO 1.6T: common questions
How big is the LightRail LPO 1.6T PCB?
The LightRail LPO 1.6T measures 420 × 355 mm, has 32 copper layers and is 3.48 mm thick.
How many components are on the LightRail LPO 1.6T?
2766 components, from 23 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the LightRail LPO 1.6T design files?
From the lightrail-dev/new repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the LightRail LPO 1.6T design in my own project?
The repository has no license, so all rights stay with lightrail-dev. Use it as a reference, and ask the author before reusing the design.
