A TMR angle sensor interface ASIC for in-vehicle applications with dynamic compensation for offset, gain and distortion errors to achieve very high angle accuracy performance. The SiP sensor module is connected directly (no PCB) to the automotive wiring harness.
This ASIC has an auto-calibration sequence that allows to compensate for non-idealities introduced by the magnet and mechanical (e.g. tilting) assembly process. It includes a high accuracy read-out chain (16-bit AFE), system diagnostics and HV tolerance on VCC (-18, +27V) and digital interface pins (-6V, +18V). Several diagnostic measures have been implemented to achieve ASIL-B safety level (SEooC).
High vibration tolerances and high ambient temperature (160degC operating temperature) do not allow the use of a PCB. Therefore a SiP (System-in-Package) solution is delivered with integrated SMD components for ESD/EMC, TMR sensor and the ASIC.
Analog features
- Best angle accuracy (0.2deg) on the market (2016) through dynamic compensation (during rotation)
- High angle dynamic profile (accelerations upto 300krpm/s)
- High EMC/ESD durability with only in-package components: ESD (ISO10605) and EMC (ISO11452, ISO7637, CISPR25)
- Wheatstone bridge differential chopped SINE and COSINE readout channels with 16-bit Delta-Sigma ADCs
- Active slope control (load dependent self-adjustment)
- “Beyond” AECQ-100 Grade-0 (-40C to 175C)
- Functional safety ISO26262 ASIL-B (SEooC)
- Output protocols: SENT, PWM, UVW (Hall emul.), ABZ
- 0.18um BCD process
Digital Features
- Embedded DSP
- Decimation / Filtering
- ATAN calculation (using CORDIC)
- Static compensation
- On-chip calibration procedure for EOL testing
- Calculates sensor distortion components (HD1..HD3)
- Can also compensate mechanical non-idealities like magnet tilting etc
- Dynamic compensation
- Active during normal operation (while rotating)
- Compensates for drifts of gain, offset, orthogonality, HD4 distortion parameters
- Test & memory control Digital diagnostics for ASIL B