ESP32/ATmega328 Industrial PCB Design

I’m consolidating an existing prototype into a single industrial-grade PCB that hosts an ESP32 module for wireless connectivity and an ATmega328 for deterministic tasks. The board’s main job is high-accuracy sensor data collection, but it must also drive several stepper motors, so clean analogue front-ends and rock-solid power electronics need to live happily beside 24 V motor drivers.

Scope
• Schematic capture that merges the two MCUs, level-shifting and all necessary isolation between the low-noise sensor domain and the higher-current motor domain.
• PCB layout ready for fabrication: four-layer minimum, controlled impedance where appropriate, wide creepage on the power stage, and industrial connectors (Phoenix-style) for field wiring.
• Integrated 5 V/3.3 V regulators sourced from a 24 V rail, plus reverse-polarity, surge and ESD protection.
• BOM with readily available parts and suggested alternates.
• Manufacturing files: Gerbers, drill, pick-and-place and assembly drawings.
• Brief bring-up firmware that shows sensor acquisition on the ATmega328, hands data to the ESP32 over UART/I²C, and drives a NEMA 17 stepper via a standard driver (e.g., DRV8825).

Acceptance
The design should pass basic ERC/DRC, compile in KiCad 7 (Altium acceptable if you provide a tagged release archive), and be electrically reviewed through a quick design-for-manufacture report. I’m not on a tight clock, so we can iterate on the layout until it’s production-ready; quality and maintainability trump speed.