May 28, 2015 – ams (Country Manager Jong-Deok Lee), a company specializing in high-performance analog ICs and sensors, announced that Marquardt, a company specializing in automotive devices, has adopted ams’s AS3914 NFC reader IC for a new series of contactless door locks and vehicle ignition control modules.

Markbart is a German company that supplies mechatronics expertise to leading global automotive manufacturers. The company stated that it adopted ams’ AS3914 device because it delivers highly reliable NFC coupling performance even when mounted near automotive sheet metal. The AS3914 also features lower average power consumption than competitor NFC reader ICs.

For contactless car key applications, the Markbart NFC module is mounted inside the car door handle and the vehicle center console (inside the cabin). At the door handle, the 13.56 MHz module connects to a standard NFC card (tag) or tag emulator, such as a mobile phone, smartwatch, or tablet. The driver simply touches the smartphone or similar device to the door handle. The system's operating range is approximately 4 cm. Once the identity of the authenticated tag is verified, the module commands the ECU (electronic control unit) to unlock the vehicle.

The secondary module in the sensor console performs a contactless connection with the driver's tag once again before the car starts.

The Markbart module is scheduled to be applied to next-generation production vehicles of a premium European automaker. A pre-production demo was demonstrated at the Mobile World Congress (MWC) in March 2015.

In door handle applications, NFC readers are exposed to environments where they must operate under conditions that interfere with RF transmission. The bodywork of a car door acts as an unwanted antenna, altering the direction of a significant amount of RF energy emitted by the reader. Markbart's design engineers discovered that the AS3914 provides much more predictable and reliable performance under these demanding conditions than other NFC reader ICs. This high performance is attributed to the AS3914's integration of high RF output power of up to 1W, high sensitivity, and a proprietary Automatic Antenna Tuning (AAT) function. The AAT function reduces interference caused by the vehicle's metal surfaces and compensates for distortion.

Using the AS3914, Markbart can achieve a door handle range of 4 cm under almost all operating conditions, even in automotive designs where plastic door handles are coated with chrome metal. The 4 cm door handle range is ideal for such applications as it eliminates the need for the driver to precisely position a tag or tag emulator next to the door handle, and it is also easy to use. On the other hand, it prevents the vehicle door from being inadvertently unlocked when passing near the vehicle door at a range of more than 4 cm.

Another advantage of the AS3914 is its low power consumption. The low-power capacitive/inductive wake-up function continuously scans tags and activates (wakes up) the high-power NFC transmitter when it detects that a tag is moving within range. The low-power wake-up function consumes only 5µA in capacitive mode when irradiated every 100ms.

Door handle and center console applications can be used not only with the Markbart NFC module but also with aftermarket 'contactless key' products designed to be mounted directly behind the vehicle's windshield. In this case, the module must operate in metallic environments, which require the AS3914's optimized receiver sensitivity and high RF output power.

Rene Wutte, Senior Marketing Manager at ams, said, “The automotive environment is a very difficult space for NFC devices to operate because a significant portion of it is surrounded by metal. To enable successful operation in these applications, Markbart has leveraged the unique strengths of the AS3914. ams is very pleased to be able to support a progressive company developing a completely new product in the automotive market. Markbart has opened a new path that numerous companies in the automotive industry can follow.”

Mark Bart stated, “Collaborating with ams on the AS3914 from start to finish was a very enjoyable experience. Even in the initial prototypes, we were able to achieve much greater distances when utilizing the AS3914 compared to using other competitor reader ICs. This means our design team can launch products quickly by achieving superior robustness under demanding operating conditions when building modules.”

The AS3914 is currently being supplied as a sample and is scheduled for mass production in late 2015. The AS3914 is a variant of the existing AS3911B and was developed for use in automotive applications. The test scope of AS3914 is applied to meet the requirements of automotive product manufacturers. Detailed technical information on AS3911B, which forms the basis of AS3914, can be found at http://www.ams.com/NFC/AS3911B.