The **AD8223BR-R7** is a high-performance, integrated instrumentation amplifier designed by Analog Devices. It is particularly valued in precision circuits because it can operate on a single power supply and offers a rail-to-rail output. --- ### 1. Key Technical Specifications The following table summarizes the primary electrical characteristics of the AD8223BR-R7: | Parameter | Specification | | :--- | :--- | | **Type** | Instrumentation Amplifier | | **Architecture** | 3-Op Amp Topology | | **Gain Range** | 1 to 1000 (Set by a single resistor) | | **Supply Voltage (Single)** | 3V to 24V | | **Supply Voltage (Dual)** | ±1.5V to ±12V | | **Input Bias Current** | 20 nA (Maximum) | | **CMRR (Common Mode Rejection)** | 80 dB (G=10) | | **Package / Case** | 8-SOIC (Small Outline Integrated Circuit) | | **Packaging** | Tape & Reel (R7 suffix indicates 7" reel) | --- ### 2. Functional Description The AD8223 is designed to extract small differential signals in the presence of large common-mode noise. * **Gain Programming:** The gain is calculated using the formula: `Gain = 1 + (100 kΩ / Rg)` Where `Rg` is the external resistor connected between pins 1 and 8. If no resistor is used, the gain is 1. * **Rail-to-Rail Output:** This allows the output signal to swing very close to the supply rails, maximizing dynamic range in low-voltage systems (like 3.3V or 5V logic). * **Power Efficiency:** It consumes very low quiescent current (typically 650 µA), making it suitable for battery-powered portable devices. --- ### 3. Pin Configuration (8-Lead SOIC) | Pin No. | Mnemonic | Description | | :--- | :--- | :--- | | 1, 8 | -RG, +RG | Terminals for the external gain resistor | | 2 | -IN | Inverting Input | | 3 | +IN | Non-inverting Input | | 4 | -VS | Negative Supply (or Ground in single-supply) | | 5 | REF | Reference Pin (sets the output offset voltage) | | 6 | VOUT | Output Terminal | | 7 | +VS | Positive Supply Voltage | --- ### 4. Typical Applications The AD8223BR-R7 is commonly found in environments where precision and low power are critical: * **Medical Instrumentation:** ECG and non-invasive blood pressure monitors. * **Industrial Process Control:** Bridge amplifiers for strain gauges and pressure sensors. * **Precision Data Acquisition:** Interfacing sensors with ADCs in 3V or 5V systems. * **Portable Systems:** Handheld multimeters and environmental sensors. ---