## Technical Overview of ADR3425ARJZ-R7 The **ADR3425ARJZ-R7** is a high-precision, low-power, low-noise CMOS voltage reference. It is part of the ADR34xx family from Analog Devices, specifically designed for applications where high accuracy and stability are required in a compact form factor. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Output Voltage ($V_{out}$)** | 2.5 V | | **Initial Accuracy** | ±0.1% (Maximum) | | **Temperature Coefficient** | 8 ppm/°C | | **Input Voltage Range** | 2.7 V to 5.5 V | | **Quiescent Current** | 100 µA (Maximum) | | **Output Current Drive** | ±10 mA | | **Operating Temperature** | -40°C to +125°C | | **Package Type** | SOT-23-6 (indicated by the "RJ" suffix) | --- ### 2. Core Functional Components The internal architecture of the ADR3425 includes several critical electronic stages: 1. **Band Gap Reference:** The core "engine" that generates the stable 2.5V reference voltage by utilizing the predictable thermal characteristics of silicon transistors. 2. **Error Amplifier:** Compares the output voltage against the internal reference and adjusts the output stage to maintain precision under varying loads. 3. **Output Buffer:** A high-drive stage that allows the chip to source or sink up to 10mA, enabling it to drive the reference inputs of ADCs or DACs without needing an external buffer. 4. **Trimming Circuitry:** During manufacturing, Analog Devices uses "laser trimming" to adjust internal resistors, ensuring the initial accuracy stays within the 0.1% margin. --- ### 3. Pin Configuration (SOT-23-6) | Pin No. | Name | Description | | :--- | :--- | :--- | | 1 | **TP** | Test Pin (Leave unconnected) | | 2 | **GND** | Ground | | 3 | **EN** | Enable Pin (Active high) | | 4 | **VIN** | Input Voltage Supply | | 5 | **NC** | No Connect | | 6 | **VOUT** | Reference Voltage Output | --- ### 4. Typical Application Use-Cases The ADR3425 is commonly used as a stable "yardstick" for measurement systems: * **Precision Data Acquisition:** Providing the reference voltage for 12-bit to 16-bit Analog-to-Digital Converters (ADCs). * **Industrial Process Control:** Ensuring sensors maintain calibration across wide temperature ranges. * **Battery Powered Gear:** Due to its low quiescent current (100µA), it is ideal for portable medical or handheld testing devices. --- ### 5. Part Number Breakdown * **ADR3425**: Device Series (2.5V output). * **A**: Accuracy Grade. * **RJ**: SOT-23 Package. * **Z**: RoHS Compliant (Lead-free). * **R7**: Tape and Reel packaging (7-inch reel).