Analog Devices Inc. AD7761BSTZ

Overview

AD7761BSTZ from Analog Devices is an 8-channel, 16-bit simultaneous-sampling sigma-delta ADC with per-channel Σ-Δ modulators and digital filters, delivering 97.7 dB dynamic range at 110.8 kHz input bandwidth, ±1 LSB INL, and programmable power-speed-bandwidth trade-offs. It serves as the core acquisition engine in high-fidelity multichannel data acquisition systems for industrial condition monitoring and precision medical instrumentation.

For engineers reviewing the AD7761BSTZ datasheet, AD7761BSTZ pinout, AD7761BSTZ application, or AD7761BSTZ equivalent, this page provides verified technical context, real-world design meanings of key specs, validated pin functions, confirmed alternative parts with functional distinctions, and supply-ready availability details - all grounded in the Rev. A datasheet and Analog Devices' official specifications.

Technical Context

The AD7761BSTZ implements eight independent Σ-Δ modulators with dedicated sinc5 and wideband linear-phase digital filters per channel, enabling synchronized ac/dc sampling without inter-channel skew. Its architecture supports three discrete power modes (fast/median/low) with corresponding ODRs (256/128/32 kSPS), input bandwidths (110.8/55.4/13.8 kHz), and per-channel power (51.5/27.5/9.375 mW).

Digital filtering includes a wideband antialiasing filter (±0.005 dB ripple to 102.4 kHz at 256 kSPS, 105 dB stopband attenuation) and a low-latency sinc5 path (3/ODR group delay). Each channel integrates analog precharge buffers on inputs and reference terminals to reduce current draw and mitigate switching transients.

Key Specifications

Pinout & Package

AD7761BSTZ is housed in a 64-lead LQFP package (10 mm × 10 mm body, 12 mm × 12 mm PCB footprint) with no exposed pad. Pin functions are defined per the Rev. A datasheet Section "Pin Configuration and Function Descriptions" (Page 16).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel high-precision ADC applications.

Compared with AD7761BSTZ, AD7762BSTZ offers higher resolution but sacrifices programmable bandwidth and power scaling, while ADS131M08IPBSR integrates signal conditioning at the expense of filter versatility and parallel output capability - making AD7761BSTZ optimal for applications demanding both high fidelity and adaptive performance tuning.

Availability

AD7761BSTZ is available at Aetrix Electronics and suitable for vibration monitoring systems, 3-phase power analyzers, and high-precision medical EEG/EMG equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD7761BSTZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD7761BSTZ belongs to Analog Devices' precision sigma-delta ADC product line, engineered specifically for multichannel, simultaneous-sampling data acquisition in industrial, medical, and test & measurement applications demanding high dynamic range, low latency, and flexible power management.

FAQ

What is the maximum input bandwidth supported by the AD7761BSTZ?

The AD7761BSTZ supports a maximum input bandwidth of 110.8 kHz (−3 dB point) in fast mode with the wideband digital filter enabled. This bandwidth is achieved at 256 kSPS output data rate and is confirmed in the Rev. A datasheet Table 1. The device also supports reduced bandwidths of 55.4 kHz (median mode) and 13.8 kHz (low power mode), all with corresponding ODR and power adjustments. Bandwidth scales linearly with decimation rate selection.

Does the AD7761BSTZ require an external reference voltage?

Yes, the AD7761BSTZ requires an external reference voltage applied between REFx+ and REFx− pins. The absolute reference voltage range is 1 V to (AVDD1 − AVSS), with typical operation at 4.096 V. The device includes optional precharge buffers on the reference inputs to reduce current draw and improve stability - a feature explicitly documented in the Rev. A datasheet Sections "Reference Input" and "Specifications" Table 1.

How many power modes does the AD7761BSTZ support, and what are their key trade-offs?

The AD7761BSTZ supports three hardware- or SPI-configurable power modes: fast (256 kSPS, 110.8 kHz BW, 51.5 mW/channel), median (128 kSPS, 55.4 kHz BW, 27.5 mW/channel), and low power (32 kSPS, 13.8 kHz BW, 9.375 mW/channel). These modes directly trade off output data rate, input bandwidth, and per-channel power consumption - a core architectural feature detailed in the Rev. A datasheet General Description and Specifications sections.

Can multiple AD7761BSTZ devices be synchronized for more than 8 channels?

Yes, the AD7761BSTZ supports daisy-chaining via its DRDY and DCLK signals to synchronize multiple devices. The functional block diagram (Figure 1) and Applications Information section of the Rev. A datasheet confirm that SYNC_IN/SYNC_OUT pins and DRDY-driven timing enable deterministic inter-device alignment. This allows coherent sampling across >8 channels - essential for PXI-based power analyzers and multi-axis structural health monitoring systems using AD7761BSTZ.

What digital interface options does the AD7761BSTZ provide for data readout?

The AD7761BSTZ provides two concurrent digital interface options: parallel (eight independent DOUT0–DOUT7 lines, DRDY strobe, DCLK) and serial (SPI-compatible with ST0/CS, ST1/SCLK, DEC0/SDO, DEC1/SDI). Both support CRC error checking. The Rev. A datasheet Sections "Data Interface" and "SPI Control" confirm that parallel mode delivers full 16-bit data per channel simultaneously, while SPI mode enables configuration and diagnostic access - making AD7761BSTZ adaptable to FPGA-based high-throughput systems or microcontroller-based compact DAQs.