RAA2S425B Automotive Sensor Signal Conditioner

The RAA2S4252B is a member of Renesas’ family of CMOS integrated circuits for highly accurate amplification and sensor-specific correction of differential bridge sensor signals. Featuring a maximum analog pre-amplification of 900 with analog sensor offset correction (XSOC), the RAA2S4252B is adjustable to nearly all resistive bridges.

Conditioning calculation is accomplished via a 16-bit RISC microcontroller. Calibration coefficients and configuration data are stored in the non-volatile memory (NVM), which is reliable in automotive applications.

Measured values are provided via a ratiometric analog output signal. End-of-line (EOL) calibration is also supported through this output pin via a one-wire interface (OWI). Digital calibration helps keep assembly costs low as no trimming by external devices or lasers is needed. The RAA2S4252B is optimized for harsh automotive environments by overvoltage and reverse polarity protection circuitry, excellent electromagnetic compatibility, and multiple diagnostic features.

Features and Benefits

• Compatible with all resistive pressure sensing technologies
• Extended XSOC
• Overvoltage and reverse polarity protection ±40 V, robust EMC performance, and superior diagnostic features
• Temperature sensing using PTC/Diode/PTAT/BRTC
• Effective ADC resolution 13-bits to 18-bits
• Output update rate of 100 μs in fastest mode; comparable analog bandwidth in 5 kHz region
• Ratiometric analog output (A_OUT) signal
• AECQ-100 Grade 0 qualified, offering both QM and ASIL-B variants
• Highly cost-effective solution for sensors with small BOM and EOL calibration
• Requires minimal external components (reduces BOM costs)
• Minimal EOL production costs during mass production
• Digital compensation of offset, sensitivity, temperature drift, and nonlinearity
• Ability to cover large sensor span while offering high accuracy (1.0%) over the entire temperature range (-40°C to +150°C)
• RAA2S4251 (QM, QFN-24, and bare-die), RAA2S4252 (SOP-08), and RAA2S4253 (ASIL-B, QFN-24, and bare-die) variants