**AD7928BRU: A Comprehensive Guide to Analog Devices' 8-Channel, 12-Bit SAR ADC**

In the realm of data acquisition systems, the ability to accurately convert real-world analog signals into precise digital values is paramount. The **AD7928BRU** from Analog Devices stands as a robust solution in this space, offering high performance and integration for a wide array of applications. This comprehensive guide delves into the architecture, key features, and practical considerations for utilizing this powerful analog-to-digital converter (ADC).

The AD7928BRU is an **8-channel, 12-bit successive approximation register (SAR)** ADC. It is designed to sequentially sample and convert analog inputs from up to eight single-ended channels, delivering a solid throughput of up to **1 MSPS (mega sample per second)**. This combination of channel count, resolution, and speed makes it exceptionally versatile for complex systems requiring multiple sensor inputs, such as in industrial control, medical instrumentation, and automotive systems.

Housed in a compact TSSOP-20 package, the device integrates a host of critical features that simplify system design. A key advantage is its **highly integrated system foundation**. The AD7928BRU contains an on-chip track-and-hold amplifier, a precision reference (2.5 V), and a versatile serial interface (SPI/QSPI/MICROWIRE/DSP compatible). This high level of integration reduces the bill of materials, minimizes board space, and enhances overall system reliability by limiting the number of external components required.

The ADC operates from a single **2.7 V to 5.25 V power supply**, making it suitable for both 3 V and 5 V systems. Its power consumption is a standout feature, drawing just 8 mW典型值 with a 5 V supply at 1 MSPS. Furthermore, it employs **advanced power-down modes** that reduce consumption to 1 µA典型值 when not actively converting, a critical capability for battery-powered and portable applications where energy efficiency is a primary concern.

The flexible serial interface allows for easy connection to microcontrollers and digital signal processors (DSPs). The **programmable input range** is another significant benefit. Users can select either a 0 to VREF input range or a 0 to 2 × VREF range, providing the flexibility to handle a wider variety of signal amplitudes without external conditioning circuitry. The device also offers a channel sequencer, allowing a specific set of channels to be converted in a predefined order, offloading timing tasks from the system processor.

Designing with the AD7928BRU requires attention to several factors for optimal performance. Proper **PCB layout and grounding** are essential to mitigate noise and ensure the integrity of the analog signal. Bypass capacitors should be placed as close as possible to the power supply pins. For applications involving DC measurements, the excellent **DNL (Differential Non-Linearity) of ±0.5 LSB** ensures no missing codes and superior linearity. For AC applications, its strong **SNR (Signal-to-Noise Ratio)** performance is crucial for capturing dynamic signals accurately.

In summary, the AD7928BRU is a highly capable ADC that successfully balances performance, power efficiency, and integration. Its 8-channel input, 12-bit resolution, and 1 MSPS speed make it a compelling choice for designers tackling complex multi-channel data acquisition challenges across diverse industries.

**ICGOO**DFIND: The AD7928BRU is a highly integrated, high-performance 8-channel SAR ADC from Analog Devices. Its combination of **1 MSPS throughput, low power consumption, flexible serial interface, and programmable input ranges** makes it an ideal and efficient choice for sophisticated multi-sensor measurement systems.

**Keywords:** SAR ADC, 12-Bit Resolution, 1 MSPS, Low Power Consumption, SPI Interface.