Case Study: How Fixing a Single Ground Plane Error Saved a Hardware Launch
The Problem A client approached us with a custom industrial controller board suffering from random microcontroller resets during field operation. Two previous PCB layout revisions had failed to resolve the issue, leading to costly product delays and field failures. The Diagnosis Upon conducting a thorough hardware troubleshooting and design review in KiCad , we identified two critical signal integrity flaws: A split ground plane beneath high-speed signal traces was forcing return currents to take a long, inductive path, creating severe EMI/EMC issues and ground bounce. Poor decoupling capacitor placement —located too far from the microcontroller's VCC pins—caused voltage dips during sudden switching loads. The Solution We redesigned the 4-layer PCB stackup to implement a continuous, solid ground plane with proper stitching vias. Additionally, we relocated the decoupling capacitors directly adjacent to the IC power pins to minimize loop inductance. The R...