The **AD7921ARM** from Analog Devices is a high-performance, 12-bit analog-to-digital converter (ADC) that utilizes the **successive approximation register (SAR)** architecture. This single-channel ADC is designed for applications requiring low power consumption and high-speed data acquisition, making it a versatile component in various industrial, medical, and communication systems. Housed in a compact **10-lead MSOP package**, it is well-suited for space-constrained designs.

A key feature of the AD7921ARM is its impressive **throughput rate of up to 200 kSPS**, allowing it to rapidly convert analog signals into precise digital values. It operates from a single **2.7 V to 5.25 V power supply**, enhancing its flexibility across different system voltages. The device incorporates a low-power shutdown mode, which reduces the current consumption to just 1 µA, a critical advantage for battery-powered and portable equipment.

Communication with a microcontroller or processor is streamlined through a high-speed, versatile **3-wire serial interface** compatible with SPI, QSPI, MICROWIRE, and DSP standards. The interface supports both a simple 3-wire mode for standalone operation and a more advanced daisy-chain mode for connecting multiple ADCs on a single bus, simplifying system design and reducing the number of required I/O pins.

The internal design includes a precise reference, typically set at 2.5 V, which can also be overdriven by an external reference for applications demanding higher accuracy or a specific voltage range. The ADC's input range is 0 V to VREF, and it offers excellent **AC and DC performance** with specifications like low integral nonlinearity (INL) and no missing codes, ensuring reliable and accurate data conversion.

Typical applications for the AD7921ARM span a wide range, including:

* **Data Acquisition Systems (DAS)**

* **Portable Instrumentation and Medical Devices**

* **Battery-Powered Systems**

* **Motor Control and Industrial Process Control**

* **Optical Network Control Loops**

ICGOOODFIND: The AD7921ARM stands out as an optimal solution for designers seeking a blend of **speed, accuracy, and low power consumption** in a small-form-factor ADC. Its integrated reference and flexible serial interface significantly reduce external component count and simplify design complexity, making it a go-to choice for modern embedded systems.

**Keywords:**

1. **SAR ADC**

2. **Low Power**

3. **200 kSPS**

4. **SPI Interface**

5. **12-Bit Resolution**