## Technical Overview: AD8211YRJZ-R2 The **AD8211YRJZ-R2** is a high-precision, high-voltage, bidirectional current sense amplifier manufactured by **Analog Devices**. It is specifically designed to amplify small differential voltages in the presence of high common-mode voltages. --- ### 1. Key Technical Specifications | Parameter | Value / Range | | :--- | :--- | | **Function** | High-Side Current Shunt Monitor | | **Gain (Fixed)** | 20 V/V | | **Common-Mode Voltage** | -2V to +65V (Continuous) | | **Supply Voltage Range** | 4.5V to 5.5V | | **Operating Temperature** | -40°C to +125°C | | **Package Type** | SOT-23-5 (Surface Mount) | | **Bandwidth** | 500 kHz | | **CMRR** | 120 dB (Minimum) | --- ### 2. Core Features * **High Common-Mode Rejection:** It can accurately measure current even when the line voltage fluctuates between -2V and +65V, effectively "ignoring" the high voltage and focusing on the drop across the shunt resistor. * **Precision Performance:** It features a very low offset drift (typically 1 μV/°C), ensuring accuracy across a wide range of operating temperatures. * **Buffered Output:** The output is a low-impedance voltage source, making it easy to interface directly with Analog-to-Digital Converters (ADCs) or Microcontrollers (MCUs). * **Bidirectional Capability:** While optimized for high-side sensing, it can handle small negative common-mode swings. --- ### 3. Functional Pin Configuration The device comes in a compact 5-lead SOT-23 package: | Pin Number | Name | Description | | :--- | :--- | :--- | | 1 | **OUT** | Output Voltage (Proportional to Load Current) | | 2 | **GND** | Ground | | 3 | **V+** | Supply Voltage (4.5V to 5.5V) | | 4 | **-IN** | Inverting Input (Connect to Load side of shunt) | | 5 | **+IN** | Non-inverting Input (Connect to Supply side of shunt) | --- ### 4. Typical Application Circuit The AD8211 is typically used with a small **shunt resistor ($R_{shunt}$)**. The output voltage ($V_{out}$) is calculated using the following formula: `V_out = (I_load × R_shunt) × 20` #### Example Use Cases: 1. **Transmission Control:** Monitoring solenoid currents. 2. **Battery Management:** Tracking charge and discharge cycles. 3. **Motor Control:** High-side current sensing for DC motors. 4. **Power Supply Protection:** Over-current detection. ---