The smart remote keyless entry (RKE) device includes an embedded low-power AVR 8-bit microcontroller, fractional-N RF transmitter and LF immobilizer interface in a single QFN32 package. It also integrates an AES-128 cryptography hardware engine, accessible by both the immobilizer and the RKE unit. The immobilizer interface can run in contactless mode to supply energy supply and bi-directionaldata transmission through the 125kHz LF link. The device designed for automotive applications that require extremely low power consumption, and immobilization and RKE functions in single key. The device provides all the necessary circuitry for the complete RKE application.