TDK Corporation complements the existing TMR sensor portfolio with the new Micronas signal-conditioning integrated circuit (IC) ASA 2310 for high-speed automotive and industrial electric motor applications. ASA 2310 is a low-drift, low-noise, customer-programmable TMR front-end IC with differential or single-ended SIN/COS inputs and analog outputs. Samples of ASA 2310 are now available. The start of production is planned for the end of 2023.

The ASA 2310 is designed to interface with the high-precision analog TMR sensors of the TAS family. The sensors, powered and monitored by the ASA 2310, are detecting the magnetic-field direction in the x-y plane and provide a SIN/COS analog voltage output which is used as input for the ASA 2310. The sensor interface and signal conditioning of the ASA 2310 are optimized for the TMR-Bridge signals. Major characteristics like gain, offset, (absolute) 0-angle, and orthogonality can be adjusted using the integrated signal path by programming the non-volatile memory of the ASA 2310. The different coarse gain settings ensure that the device can support various TMR full- and half-bridges from TDK. The amplified single or differential-ended output signals of the ASA 2310 can be used to calculate the rotation angle of a magnet with very high accuracy by an external A/D converter and an electronic control unit (ECU).

New rotor position sensing solutions based on the ASA 2310 offer a high resolution and accurate position measurement at very high rotation speeds of up to 650,000 rpm. This enables high-speed motors to maximize torque and increase efficiency which is essential for hybrid and electric vehicles to obtain maximum range. In addition, the sensor system configuration works independently of the motor pole pair number and therefore does not require complex hardware changes, a major advantage over inductive resolver technologies. This gives more flexibility in the development of the hybrid and electric powertrains of the future.

With its overvoltage and reverse polarity protection (+/-18V) the ASA 2310 features excellent robustness against electrical challenges. Compared to off-the-shelf amplifier ICs, the ASA 2310 is more appropriate for safety-critical applications since the signal-conditioning IC simplifies the external circuitry resulting in a low FIT rate. Moreover, the total system size, BOM, and assembly process costs are reduced.

This product is defined as SEooC (Safety Element out of Context) ASIL B ready according to ISO 26262. To enable the most efficient failure localization and elimination, the ASA 2310 provides a single-point fault metric (SPFM) of more than 97% which exceeds even the standard requirements of an ASIL B classification. If ASIL decomposition is applied on the system level, the IC can be integrated into systems up to ASIL D. Besides various integrated safety monitoring of the IC itself and the external TMR-bridges, the ASA 2310 features an optional and unique fluxless self-test allowing the system to test the full signal path inside the device before the ordinary operation starts. In an application setup, the test can be used to check the integrity of the whole signal path including wiring, external output capacitors, and ECU. Finally, the variety of safety monitoring helps to increase diagnostic coverage and simplify the external safety supervision on the ECU side.