The **AD22283-B-R2** is a specialized high-performance, dual-axis accelerometer designed primarily for automotive safety systems, specifically for airbag deployment and electronic stability control. --- ### 1. Device Overview The AD22283 is part of Analog Devices' iMEMS (integrated Micro-Electro-Mechanical Systems) family. It integrates both the mechanical sensor and the signal conditioning circuitry on a single monolithic chip. | Feature | Specification (Typical) | | :--- | :--- | | **Axis Type** | Dual-Axis (X and Y) | | **Measurement Range** | Low g-range (typically ±50g or ±250g depending on specific trim) | | **Output Type** | Analog voltage | | **Package** | 8-Lead SOIC_N | | **Technology** | iMEMS Monolithic Silicon | --- ### 2. Key Internal Components The part consists of two primary functional blocks: #### A. The Mechanical Sensor (MEMS) * **Structure:** A surface-micromachined polysilicon structure built on top of a silicon wafer. * **Function:** Polysilicon springs suspend the structure over the surface of the wafer and provide a resistance against acceleration forces. * **Detection:** Deflection of the structure is measured using a differential capacitor that consists of independent fixed plates and plates attached to the moving mass. #### B. The Signal Conditioning Circuitry * **Demodulator:** Converts the capacitive change into a voltage signal. * **Bessel Filter:** A 400Hz (typical) 2-pole low-pass filter is often integrated to provide antialiasing and noise reduction. * **Temperature Compensation:** Internal circuitry adjusts for sensitivity and offset changes caused by temperature fluctuations, ensuring reliability in harsh automotive environments. --- ### 3. Pin Configuration (8-Lead SOIC) Typical pin assignments for this series: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **ST** | Self-Test Input (Checks electromechanical systems) | | 2 | **X_OUT** | Analog output voltage for X-axis | | 3 | **Y_OUT** | Analog output voltage for Y-axis | | 4 | **COM** | Common/Ground | | 5 | **Vcc** | Supply Voltage (Typically 5V) | | 6-8 | **NC/Ref** | No Connection or Voltage Reference | --- ### 4. Application Context The "B-R2" suffix usually denotes the performance grade and the packaging format (Reel size). This specific part is engineered for: * **Impact Sensing:** Detecting rapid deceleration for airbag triggering. * **Vibration Monitoring:** High-precision industrial machinery monitoring. * **Stability Systems:** Detecting lateral vehicle skidding. ---