The **ADR5040BRTZ-R2** is a high-precision shunt voltage reference manufactured by Analog Devices. It is designed for space-constrained applications requiring high stability and low power consumption. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Output Voltage ($V_{out}$)** | 2.048 V | | **Initial Accuracy** | ±0.1% (Grade B) | | **Temperature Coefficient** | 75 ppm/°C | | **Operating Current Range** | 50 µA to 15 mA | | **Output Noise** | 120 µV p-p (0.1 Hz to 10 Hz) | | **Operating Temperature** | -40°C to +125°C | | **Package Type** | SOT-23-3 | --- ### 2. Electronic Characteristics The ADR5040 operates as a **Shunt Reference** (similar to a Zener diode). It maintains a constant voltage across its terminals as long as the current stays within the 50 µA to 15 mA range. * **Low Quiescent Current:** It can operate with as little as 50 µA, making it ideal for battery-powered handheld devices. * **No Output Capacitor Required:** Unlike many other references, the ADR5040 is stable without an external output capacitor, though one can be added to reduce noise. * **Precision Output:** The 2.048 V output is specifically chosen because it aligns perfectly with ADC (Analog-to-Digital Converter) scales where 1 LSB (Least Significant Bit) equals exactly 1 mV or 0.5 mV. --- ### 3. Application Circuitry To use this part, you must place a current-limiting resistor ($R_{set}$) between the input supply and the device. ```text Input (Vin) ----[ R_set ]----+---- Output (2.048V) | [ ADR5040 ] | GND ``` **Formula for Resistor Selection:** $R_{set} = \frac{V_{in} - V_{out}}{I_{load} + I_{ref}}$ *Where $I_{ref}$ should be at least 50 µA.* --- ### 4. Typical Applications * **Portable Instrumentation:** Multimeters and handheld sensors. * **Data Acquisition Systems:** Providing a stable reference for ADCs and DACs. * **Industrial Process Control:** Precise monitoring of 4-20mA loops. * **Medical Equipment:** Low-power diagnostic tools.