AI Edge Computing Platform (Xavier EVK)

Project Overview

NimblePCB partnered with an AIoT solutions provider to develop the PCB for their edge AI computing evaluation kit based on NVIDIA Jetson Xavier. The board serves as a development and deployment platform for AI inference workloads in industrial vision, autonomous vehicles, and smart city applications.

Challenge

• Ultra-fine-pitch BGA: The Jetson Xavier module connector required 0.5mm pitch BGA fanout with over 600 pins, demanding HDI construction with microvias.
• High-speed interfaces: Multiple PCIe Gen3/Gen4 lanes, USB 3.2, and MIPI CSI camera interfaces all required precise impedance control and crosstalk management on a dense board.
• Power delivery: The Xavier module draws up to 30W under full AI inference load, requiring a robust PDN (Power Delivery Network) with low-impedance planes and decoupling strategy.
• Thermal constraints: Edge deployment means limited cooling options. The PCB needed to serve as part of the thermal solution, conducting heat away from the module.

Solution

NimblePCB’s HDI manufacturing capabilities were critical to meeting the demanding requirements of this AI platform:

• 12-layer HDI stackup: 2+N+2 HDI construction with stacked microvias for BGA fanout. Laser-drilled 4mil microvias with copper-filled via-in-pad for maximum routing density.
• Signal integrity engineering: Simulated and optimized all high-speed differential pairs. PCIe Gen4 traces routed with 85-ohm differential impedance, length-matched within 2 mil per pair.
• Robust PDN: Multiple power plane pairs with embedded capacitance. Strategic decoupling capacitor placement validated through PDN impedance simulation.
• Thermal integration: 2oz copper on internal ground planes for heat spreading. Thermal via arrays under the module area connect to exposed copper on the bottom side for heatsink attachment.

PCB Specifications

Results

• All high-speed interfaces passed compliance testing at maximum data rates
• AI inference benchmark performance matched NVIDIA reference design specifications
• Thermal solution maintained module below 80C at sustained 30W load
• Platform adopted by 15+ customer development teams within first 6 months