Analog Devices Inc. AD7716BSZ

Overview

AD7716BSZ from Analog Devices is a 4-channel, 22-bit sigma-delta analog-to-digital converter (ADC) with integrated digital filtering, designed for high-precision, low-frequency signal acquisition in biomedical and instrumentation systems. It delivers 105 dB usable dynamic range at 146 Hz input bandwidth, supports programmable filter cutoff from 36.5 Hz to 584 Hz, and features cascading capability via CASCIN/CASCOUT pins for multi-device channel expansion.

For engineers reviewing the AD7716BSZ datasheet, AD7716BSZ pinout, AD7716BSZ application, or AD7716BSZ equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative options, and supply-ready availability details - all grounded in the official AD7716 Rev. A datasheet and Analog Devices' product documentation.

Technical Context

The AD7716BSZ implements four independent second-order sigma-delta modulators with on-chip sinc³ digital filters, enabling simultaneous sampling across AIN1–AIN4 without multiplexing-induced settling errors. Its digital filter cutoff is controlled by FC2–FC0 bits in the control register, directly determining output update rate (e.g., 2232 Hz at 584 Hz cutoff) and absolute group delay (0.675 ms at that setting).

It operates in master or slave serial interface mode via the MODE pin, with five-line serial I/O (SCLK, SDATA, TFS, RFS, DRDY) supporting easy integration into DSP/microcontroller systems. The device uses ±5 V dual supplies (AVDD/DVDD = +5 V, AVSS = –5 V), features 0.003% FSR integral nonlinearity, and guarantees no missed codes to 21 bits at 146 Hz filter setting.

Key Specifications

Pinout & Package

The AD7716BSZ is packaged in a 44-pin Plastic Quad Flatpack (PQFP), RoHS-compliant and rated for –40°C to +85°C operation. Pin assignments are validated per Analog Devices AD7716 Rev. A datasheet Figure 7 (PQFP PINOUT) and PIN DESCRIPTION table.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution, multi-channel sigma-delta ADC applications.

Compared with AD7739BRUZ and ADS1258IPWR, the AD7716BSZ uniquely combines true 4-channel simultaneity, hardware-supported daisy-chaining, and factory-calibrated sinc³ filtering - reducing system-level timing validation effort and eliminating host-side filter development for low-bandwidth precision acquisition.

Availability

AD7716BSZ is available at Aetrix Electronics and suitable for biomedical data acquisition, seismic monitoring, and high-accuracy process control applications requiring stable component supply, long-lifecycle support, and traceable sourcing.

Supply support for AD7716BSZ 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 Wilmington, MA.

The AD7716BSZ belongs to Analog Devices' precision sigma-delta ADC product line, engineered specifically for wide-dynamic-range, low-frequency measurement in clinical, geophysical, and industrial instrumentation where DC accuracy and channel coherence are critical.

FAQ

What is the maximum guaranteed usable dynamic range of the AD7716BSZ and under what conditions?

The AD7716BSZ achieves a maximum guaranteed usable dynamic range of 111 dB when configured with a 36.5 Hz digital filter cutoff frequency, measured using a 2.5 V reference and ±2.5 V input range. This corresponds to 5 µV rms noise and is specified across the full operating temperature range (–40°C to +85°C). The AD7716BSZ datasheet Table I confirms this value as a guaranteed minimum, not a typical figure.

Does the AD7716BSZ support true simultaneous sampling across all four channels?

Yes, the AD7716BSZ performs true simultaneous sampling using four independent sigma-delta modulators - one per channel (AIN1–AIN4). Unlike multiplexed ADCs, it does not share a single conversion core; each channel samples continuously and concurrently. This eliminates inter-channel skew and avoids settling delays when switching between inputs, making the AD7716BSZ suitable for coherent multi-lead ECG or synchronized sensor arrays.

How does the CASCIN/CASCOUT functionality work in a multi-AD7716BSZ system?

In a multi-device configuration, CASCIN is an active-high level-triggered input that enables the output data stream. When one AD7716BSZ completes its 4-channel data transfer, its CASCOUT pin goes high, which can be wired to the CASCIN of the next AD7716BSZ to trigger its transmission. This hardware handshaking ensures deterministic, glitch-free daisy-chaining of up to 32 devices without software coordination or frame synchronization overhead.

What are the power supply requirements for reliable operation of the AD7716BSZ?

The AD7716BSZ requires three dedicated supply rails: AVDD = +4.75 V to +5.25 V (analog positive), DVDD = +4.75 V to +5.25 V (digital positive), and AVSS = –4.75 V to –5.25 V (analog negative). AGND and DGND must be tied together at a single point. The device draws 4.8 mA typical IDD and 1.8 mA typical ISS, totaling ~35 mW typical power consumption. Supply rejection is –70 dB typical, so clean, well-decoupled ±5 V supplies are mandatory for achieving datasheet performance.

Can the AD7716BSZ operate without an external clock source?

Yes, the AD7716BSZ supports self-contained clock generation: connect a parallel-resonant crystal between CLKOUT and CLKIN pins to enable the internal oscillator. With a typical 8 MHz crystal, the device generates its master clock internally and achieves full specification performance (e.g., 584 Hz filter cutoff, 2232 Hz output rate). No external clock generator or buffer is needed - simplifying layout and reducing BOM count in space-constrained designs using the AD7716BSZ.