Analog Devices Inc. AD7715ARZ-3REEL

Overview

AD7715ARZ-3REEL from Analog Devices is a 16-bit sigma-delta analog-to-digital converter optimized for low-frequency precision measurement. It integrates a programmable-gain amplifier (gains 1/2/32/128), differential analog and reference inputs, on-chip digital filtering, and a three-wire SPI-compatible serial interface. Operating at 3 V with ≤450 µA supply current, it directly digitizes microvolt-level transducer outputs in industrial sensor conditioning systems.

For engineers reviewing the AD7715ARZ-3REEL datasheet, AD7715ARZ-3REEL pinout, AD7715ARZ-3REEL application, or AD7715ARZ-3REEL equivalent, key selection criteria include its guaranteed 16-bit no-missing-codes performance, ±0.0015% integral nonlinearity, 50 Hz/60 Hz notch filter programmability, and support for unipolar (0–1.25 V) and bipolar (±1.25 V) input ranges referenced to AGND.

Technical Context

The AD7715ARZ-3REEL employs a charge-balancing sigma-delta modulator with on-chip digital filtering, where the first notch frequency is software-programmable to set output update rate and line-frequency rejection. Its analog front end includes a buffered or unbuffered differential input stage and separate differential reference inputs, enabling high CMR (>90 dB dc, >150 dB at 50/60 Hz) and precise ratiometric measurement.

It features self-calibration and system calibration modes to eliminate offset and gain errors, with drift specifications of 0.2 µV/°C (unipolar offset) and 0.2 ppm/°C (gain) at 3 V operation. The device supports master clock frequencies from 400 kHz to 2.4576 MHz and operates across −40°C to +85°C.

Key Specifications

Pinout & Package

AD7715ARZ-3REEL is housed in a 16-lead SOIC_W (wide-body) package, 0.3 inch width, RoHS-compliant, with exposed pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision sigma-delta ADC applications.

Compared with AD7714ARZ and ADS124S08IPW, the AD7715ARZ-3REEL delivers the lowest system BOM cost for single-channel 16-bit measurement, with minimal layout area and established qualification history in harsh industrial environments.

Availability

AD7715ARZ-3REEL is available at Aetrix Electronics and suitable for pressure transducers, RTD temperature sensors, and smart 4–20 mA transmitters requiring stable component supply and long-term industrial lifecycle support.

Supply support for AD7715ARZ-3REEL 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 AD7715ARZ-3REEL belongs to Analog Devices' precision sigma-delta ADC product line, engineered specifically for low-frequency, high-accuracy industrial measurement where noise immunity, calibration integrity, and low-power operation are critical.

FAQ

What is the maximum master clock frequency supported by the AD7715ARZ-3REEL?

The AD7715ARZ-3REEL supports master clock frequencies up to 2.4576 MHz for full specification compliance. It is production-tested at this frequency and characterized to operate down to 400 kHz. Operation above 2.4576 MHz is not guaranteed and may impact INL, noise, or timing margins. Always verify timing parameters in Table 4 of the Rev. E datasheet when selecting fCLKIN.

Does the AD7715ARZ-3REEL require an external reference voltage?

Yes, the AD7715ARZ-3REEL requires an external reference voltage applied differentially between REF IN(+) and REF IN(–). For the AD7715-3 variant (which AD7715ARZ-3REEL implements), the nominal reference is 1.25 V. The device does not include an internal reference; using the specified 1.25 V reference ensures full accuracy per datasheet specifications including ±0.0015% INL and guaranteed 16-bit no missing codes performance.

Can the AD7715ARZ-3REEL interface directly with a microcontroller GPIO without level-shifting?

Yes, the AD7715ARZ-3REEL logic inputs (CS, SCLK, DIN, RESET) accept 3 V CMOS levels, and outputs (DOUT, DRDY, MCLK OUT) are 3 V compatible with 0.4 V VOL and DVDD − 0.6 V VOH. When DVDD = 3 V, these levels align directly with standard 3 V microcontroller I/O, eliminating need for level shifters. Ensure proper decoupling and adhere to timing parameters t3–t9 for reliable communication.

How does the AD7715ARZ-3REEL handle 50 Hz and 60 Hz interference?

The AD7715ARZ-3REEL achieves 98 dB normal-mode and 150 dB common-mode rejection at 50/60 Hz via its programmable digital filter notch. By configuring the filter cutoff (via the on-chip control register), users can place the first notch precisely at 50 Hz or 60 Hz - rejecting mains-borne noise without external analog filters. This is validated under conditions specified in Tables 1 and 2 of the datasheet with appropriate gain and clock settings.

Is the AD7715ARZ-3REEL pin-compatible with other AD7715 variants like AD7715BN?

No, the AD7715ARZ-3REEL is not pin-compatible with the obsolete AD7715BN (16-lead PDIP). While both share identical pin functions and numbering per Figure 3, the AD7715BN uses a through-hole PDIP package whereas AD7715ARZ-3REEL uses a surface-mount 16-lead SOIC_W package with different mechanical dimensions, thermal characteristics, and soldering requirements. PCB layout and assembly processes must be redesigned for the SOIC variant.