The Montreal subway ticket uses NFC technology through a small chip that communicates with the turnstile, allowing data exchange between the reader and the ticket over a short distance through magnetic fields. The NFC chip is extremely small and transparent to the user, providing basic data to allow entry to the subway. The chip lacks advanced security features but has unique functions such as a unique ID code, password-protected memory, and one-way counters for specific uses. The chip’s structure includes digital logic, analog circuitry, and EEPROM storage, all implemented with standard-cell logic using NMOS and PMOS transistors.
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