ACCESS CONTROL · PCB · NETWORKING
Ethernet & Wi-Fi Access Control Panel
Network-connected access-control hardware supporting 2/4 doors, with Wiegand interfaces, relay outputs, and an EMC/ESD protection approach.
Field control on one board
The panel was developed to manage readers, door states, request-to-exit inputs, and lock relays centrally in two- or four-door installations. Ethernet and Wi-Fi access scenarios were addressed at system level, while the board's wired connection uses W5500-based Ethernet.
Readers and field connections
Four Wiegand reader ports expose D0, D1, LED, BEEP, power, and ground. Door-contact and request-to-exit inputs sit alongside tamper and fire inputs, with four dry-contact SPDT relay outputs on the same board.
Control and communication
The STM32F407VGT6 works with a W5500 Ethernet interface, isolated RS485, a DS3231 real-time clock, W25Q64 external flash, and AT24C256 EEPROM. This architecture combines network communication, event storage, and peripheral control on one board.
Protection for field conditions
The power tree generates 5 V and 3.3 V rails from a 12 V input. Reverse-polarity protection, individual PTC fuses for reader supplies, optoisolation, and TVS/ESD protection on field lines form the board's electrical-protection strategy.
Outcome
The project resulted in completed access-control hardware that combines two- or four-door support and multiple field interfaces on one board. The layout keeps field connections readable and serviceable while placing protection close to the relevant interfaces.