Analog Devices Inc. AD7475ARZ

Overview

AD7475ARZ from Analog Devices is a 12-bit, single-supply successive-approximation ADC with 1 MSPS throughput, 68 dB SINAD at 300 kHz, ±1.5 LSB INL (A-grade), and operation from 2.7 V to 5.25 V. It features an external 2.5 V reference input (REF IN), VDRIVE for independent logic-level interfacing, and no pipeline delay-used in portable medical sensors and battery-powered data loggers requiring precise, low-power analog digitization.

For engineers reviewing the AD7475ARZ datasheet, AD7475ARZ pinout, AD7475ARZ application, or AD7475ARZ equivalent, this page delivers verified specifications, SOIC-8 pin mapping, real-world use cases in instrumentation and mobile comms, and two validated alternative parts with documented functional and architectural distinctions.

Technical Context

The AD7475ARZ implements a capacitive DAC-based successive-approximation architecture with on-chip track-and-hold, sampling on the falling edge of CS and completing conversion in exactly 16 SCLK cycles. Its analog input range is strictly 0 V to REF IN (2.5 V ±1%), and it uses straight binary coding with LSB = V_REF/4096.

It supports SPI-/QSPI-/MICROWIRE-/DSP-compatible serial interface timing, with VDRIVE decoupled from VDD to enable direct interfacing to 3 V or 5 V processors. Power management includes three modes: normal (1.5 mA @ 3 V), partial power-down (100 µA static), and full shutdown (1 µA).

Key Specifications

Pinout & Package

AD7475ARZ is housed in an 8-lead SOIC package (body width 3.9 mm, JEDEC MS-012), RoHS-compliant, with standard surface-mount footprint and thermal impedance θ_JA = 157°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit SAR ADC applications.

Compared with AD7475ARZ, AD7476ARZ sacrifices VDRIVE flexibility for tighter supply tolerance, while ADS7822U trades external reference control for lower power and smaller footprint-making AD7475ARZ optimal when programmable full-scale range and mixed-voltage compatibility are design priorities.

Availability

AD7475ARZ is available at Aetrix Electronics and suitable for battery-powered systems, portable medical instruments, and industrial field transmitters requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for AD7475ARZ 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, with R&D and manufacturing operations worldwide.

The AD7475ARZ belongs to Analog Devices' precision SAR ADC product line, engineered for low-power, high-throughput digitization in portable and energy-constrained applications where accuracy, small size, and flexible interfacing are critical.

FAQ

What is the reference configuration for AD7475ARZ?

The AD7475ARZ requires an external 2.5 V ±1% reference applied to the REF IN pin (Pin 1). This reference defines the full-scale analog input range as 0 V to 2.5 V. A minimum 0.1 µF decoupling capacitor must be placed between REF IN and GND to ensure stable conversion accuracy and low noise performance across temperature and supply variations. The AD7475ARZ does not include an internal reference.

Does AD7475ARZ support true 1 MSPS continuous sampling?

Yes, AD7475ARZ achieves 1 MSPS continuous throughput when operated with a 20 MHz SCLK and VDD between 2.7 V and 5.25 V. Conversion time is fixed at 16 SCLK cycles (800 ns max), and the device has no pipeline delay-each CS-initiated conversion yields a valid 12-bit result after exactly 16 clock edges. Real-world sustained rate depends on host processor's ability to issue CS pulses every 1 µs.

How does VDRIVE function in AD7475ARZ?

VDRIVE (Pin 6) sets the logic threshold for all digital pins (CS, SCLK, SDATA) independently of VDD. For example, AD7475ARZ can run its analog core at 5 V (VDD = 5 V) while interfacing directly to a 3.3 V microcontroller by tying VDRIVE to 3.3 V-eliminating external level shifters. VINH = VDRIVE − 1 V and VINL = 0.4 V ensure robust noise margins across both supply domains.

What power modes does AD7475ARZ offer, and how are they controlled?

AD7475ARZ provides three power modes controlled entirely via the serial interface: Normal Mode (full operation), Partial Power-Down (reduced current during idle SCLK periods), and Full Power-Down (1 µA max, entered by holding CS high for >100 ns after conversion). No dedicated control register is needed-mode transitions occur automatically based on CS timing and SCLK activity per the datasheet timing diagrams.

Is AD7475ARZ pin-compatible with AD7495ARZ?

No, AD7475ARZ and AD7495ARZ are not pin-compatible. AD7475ARZ uses Pin 1 as REF IN (external reference input), whereas AD7495ARZ uses Pin 1 as REF OUT (internal 2.5 V reference output). Swapping them without PCB modification causes incorrect reference connection and invalid conversions. Both share identical SOIC-8 footprints and pinouts *except* for Pin 1 functionality-requiring layout change for substitution.