ATA5795 is a smart Remote Keyless Entry (RKE) device that includes an embedded ultra-low-power AVR 8-bit microcontroller, a fractional-N RF transmitter and an LF immobilizer interface in a single QFN32 package. Furthermore, the device has an integrated AES-128 cryptography hardware engine, which is accessible by both the immobilizer and the RKE unit. The immobilizer interface can run in contactless mode, allowing energy supply and data transmission via the LF link. The ATA5795 is designed for automotive applications that necessitate both immobilization and Remote Keyless Entry functions in one single key. It conforms to requirements of extremely low power consumption and provides all the necessary circuitry for the entire application.