## Overview of the ADR3440ARJZ-R2 The **ADR3440ARJZ-R2** is a high-precision, low-power, low-dropout CMOS voltage reference. Manufactured by Analog Devices, it is part of the ADR34xx family, specifically designed for high accuracy and stability in space-constrained applications. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Output Voltage ($V_{out}$)** | 4.096 V | | **Initial Accuracy** | ±0.1% (Maximum) | | **Temperature Coefficient** | 8 ppm/°C (Maximum) | | **Input Voltage Range** | 4.3 V to 5.5 V | | **Supply Current** | 100 µA (Maximum) | | **Output Current Capability** | 10 mA (Source) / -3 mA (Sink) | | **Operating Temperature** | -40°C to +125°C | | **Package Type** | 6-Lead SOT-23 | --- ### 2. Core Functional Features * **High Precision:** The 4.096V output is specifically chosen because it aligns perfectly with the scaling of 12-bit, 14-bit, and 16-bit Analog-to-Digital Converters (ADCs), where $1 \text{ LSB}$ becomes a clean power of 2. * **Low Dropout:** It requires very little "headroom" between the input and output voltage (only about 200mV), allowing it to operate efficiently in battery-powered systems. * **Low Noise:** Designed to minimize electrical noise, ensuring that the reference voltage does not jitter or interfere with high-resolution measurements. * **No External Capacitor Required:** While many references require a large output capacitor for stability, the ADR3440 is stable with or without one, saving PCB space. --- ### 3. Pin Configuration (SOT-23) | Pin No. | Name | Description | | :--- | :--- | :--- | | 1 | **V_IN** | Input Voltage Supply | | 2 | **GND** | Ground | | 3 | **EN** | Enable Pin (Active High) | | 4 | **NC** | No Connect | | 5 | **NC** | No Connect | | 6 | **V_OUT** | Reference Output Voltage | --- ### 4. Common Applications 1. **Precision Data Acquisition:** Providing the reference floor for ADCs and DACs. 2. **Industrial Instrumentation:** Used in process control transmitters and handheld test equipment. 3. **Medical Equipment:** Vital for stable readings in patient monitoring devices. 4. **Battery Management:** Monitoring cell voltages with high thermal stability. --- ### 5. Part Number Breakdown ```text ADR 34 40 ARJZ - R2 | | | | | | | | | └── 7" Reel (250 units) | | | └── Package Code (SOT-23) | | └── Voltage Identifier (40 = 4.096V) | └── Series Family (CMOS Low Power) └── Analog Devices Reference ```