**AD7655ACP: A Comprehensive Guide to Analog Devices' 16-Bit Simultaneous Sampling SAR ADC**

In the realm of data acquisition systems, particularly those demanding precise multi-channel monitoring, the ability to capture multiple analog signals at the exact same instant is paramount. The **AD7655ACP** from Analog Devices stands as a pivotal solution, a high-performance, 16-bit, **6-channel simultaneous sampling** SAR ADC engineered to meet this critical need. This integrated circuit (IC) is designed for applications where understanding the phase relationship between multiple inputs is essential, such as in power quality measurement, multi-axis motion control, and advanced instrumentation.

**Architecture and Key Features**

The core of the AD7655's functionality lies in its innovative architecture. It incorporates six individual, high-speed, 16-bit sampling ADCs, each paired with its own sample-and-hold amplifier. This design is what enables **true simultaneous sampling** across all six channels; a single CONVST (convert start) signal initiates the sampling process for every channel at once, freezing the analog inputs for conversion without any temporal skew.

Housed in a 64-lead LQFP package (denoted by the "CP" suffix), the AD7655ACP offers a robust set of features:

* **High Resolution and Accuracy:** It provides true 16-bit resolution with no missing codes, ensuring high accuracy in the digitized output.

* **Fast Throughput Rate:** The device supports a maximum throughput of **250 kSPS per channel**, allowing for the rapid digitization of dynamic signals.

* **Low Power Consumption:** Utilizing an advanced CMOS process, it operates with very low power dissipation, a key advantage in portable or power-sensitive equipment.

* **Flexible Supply Operation:** It can operate from a single 5 V supply or dual ±5 V supplies for bipolar input ranges.

* **Integrated Reference and Buffer:** The inclusion of an on-chip 2.5 V reference and buffer simplifies system design and reduces the external component count.

**Applications and System Integration**

The **AD7655ACP** is exceptionally well-suited for complex three-phase power systems. It is ideal for **power quality measurement**, energy metering, and protective relay systems, where it can simultaneously sample all three phase voltages and currents. Other critical applications include:

* Multi-axis positioning and motion control systems

* Data acquisition systems (DAQ) and precision instrumentation

* Sonar and radar beam-forming systems

* Medical imaging equipment

Integration into a system is streamlined through a parallel interface, compatible with microprocessors (µPs) and digital signal processors (DSPs). For systems requiring isolation, the parallel interface can be easily interfaced with digital isolators.

**ICGOODFIND**

The **AD7655ACP** is a cornerstone component for engineers designing high-performance, multi-channel data acquisition systems. Its **unmatched channel integration**, **true simultaneous sampling capability**, and **16-bit precision** make it an indispensable solution for accurately capturing the state of complex analog systems in a single time slice. It effectively balances performance, power, and integration, solidifying its status as a go-to ADC for demanding industrial and instrumentation applications.

**Keywords:**

1. Simultaneous Sampling SAR ADC

2. 16-Bit Resolution

3. Multi-Channel Data Acquisition

4. Power Quality Measurement

5. Analog Devices