November 2011:- Atmel, a leader in microcontroller and touch technology solutions, a new ultra-low power AVR microcontroller (MCU) with secure AES-128 immobilizer protocol stack. The Atmel ATA5790N microcontroller includes LF immobilizer functionality and a 3D LF receiver in a single 5mm x 7mm package. When combined with the companion device ATA5830 RF transmitter, the Atmel ATA5790N is ideal for high-volume uni- and bi-directional car key fobs for passive entry and passive start systems.

Microcontroller-based Secure AES-128 Immobilizer for Car Key Fob ApplicationsThe AVR microcontroller provides 16k Flash and 2k EEPROM. Within the 16k Flash, 14kB is available for the application software, while 2kB is available for the immobilizer functionality. The core is surrounded by specific hardware accelerators which allows for an implementation of any immobilizer protocol in the software without the typical current consumption impact.

The Atmel ATA5790N microcontroller offers the lowest current consumption in the industry, with a listening mode of less than 4.5 microampere. Lower current consumption can extend the battery life significantly for car key fobs. The 3D LF RSSI measurement with maximum sensitivity allows for a quick and accurate key fob localization.

The built-in AES-128 cryptographic engine, along with the Atmel protocol stack, provides maximum security protection with fast authentication time which is critical to immobilizer systems. As an open-source solution, AES-128 encryption is far more secure than competitive proprietary solutions since peer reviewing increases fault detection.

In addition, the Atmel AES-128 immobilizer protocol stack is the first open source stack to allow interoperability between different semiconductor vendors. With current conventional solutions, the necessary communication protocol layers are closed source or patented, which prevents car manufacturers from adopting multi-vendor sourcing strategies. This convention method also leads to lock-in situations that are counterproductive when quality problems arise.

The ATA5790N microcontroller is a new member of Atmel’s broad family of transmitter, receiver and transceiver devices for car access applications. This enables designers to create complete system solutions with devices that provide a perfect combination. The same software and tools can be used, thus increasing the ease-of-use and reducing the overall time-to-market.