Analog Devices Inc. AD7475ARMZ

Overview

AD7475ARMZ from Analog Devices is a 12-bit, single-supply successive-approximation ADC with 1 MSPS throughput, 68 dB SINAD at 300 kHz input, ±1.5 LSB INL (A-grade), and operation from 2.7 V to 5.25 V. It uses an external 2.5 V reference, supports SPI-/QSPI-/MICROWIRE-compatible serial interface, and targets precision data acquisition in space-constrained battery-powered systems.

For engineers reviewing the AD7475ARMZ datasheet, AD7475ARMZ pinout, AD7475ARMZ application, or AD7475ARMZ equivalent, key selection criteria include its 1 MSPS no-pipeline-delay conversion, VDRIVE-independent 3 V/5 V logic interfacing, 4.5 mW power at 3 V/1 MSPS, and MSOP-8 package compatibility with low-power sensor front-ends and portable instrumentation.

Technical Context

The AD7475ARMZ implements a capacitive DAC-based successive-approximation architecture with on-chip track-and-hold, enabling accurate sampling on the falling edge of CS and full conversion in 16 SCLK cycles. Its analog input range is strictly 0 V to REF IN (2.5 V ±1%), and it requires no external reference buffer.

It features three power modes: normal (1.5 mA at 3 V/1 MSPS), partial power-down (450 µA at 100 kSPS), and full shutdown (1 µA). The VDRIVE pin decouples logic I/O voltage (2.7 V–5.25 V) from VDD, allowing direct interfacing with 3 V microcontrollers even when VDD = 5 V.

Key Specifications

Pinout & Package

AD7475ARMZ is housed in an 8-lead MSOP package (3.0 mm × 3.0 mm, 0.65 mm pitch), optimized for compact PCB layouts in portable electronics. Thermal resistance θJA = 205.9°C/W enables reliable operation at ambient temperatures up to +85°C without forced airflow.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7475ARMZ, AD7476ARMZ offers higher speed within identical form factor and interface, while ADS7822U trades speed and package size for lower unit cost-making AD7475ARMZ the optimal balance of performance, power, and miniaturization for modern portable instrumentation.

Availability

AD7475ARMZ is available at Aetrix Electronics and suitable for battery-powered systems, portable medical instruments, and industrial handheld testers requiring stable component supply, long-lifecycle support, and traceable sourcing.

Supply support for AD7475ARMZ 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD7475ARMZ belongs to Analog Devices' precision SAR ADC product line, designed specifically for low-power, high-speed data acquisition in space- and energy-constrained portable and embedded systems.

FAQ

What is the maximum sample rate supported by the AD7475ARMZ?

The AD7475ARMZ supports a maximum throughput rate of 1 MSPS, achieved with a 20 MHz serial clock (SCLK) frequency and 16 SCLK cycles per conversion. This rate is fully specified across the operating temperature range (−40°C to +85°C) and supply voltages (2.7 V to 5.25 V). At lower SCLK frequencies, the throughput scales linearly-for example, 5 MHz SCLK yields ~315 kSPS. The AD7475ARMZ does not employ pipelining, so each conversion completes deterministically with no latency accumulation.

Does the AD7475ARMZ include an internal voltage reference?

No, the AD7475ARMZ does not include an internal voltage reference. It requires an external 2.5 V ±1% reference applied to the REF IN pin (Pin 1). This design allows system-level reference sharing, improved thermal drift performance via high-stability external references (e.g., AD780), and avoids the power and accuracy trade-offs of integrated references. In contrast, the pin-compatible AD7495ARMZ variant integrates a 2.5 V reference on-chip and exposes it via REF OUT (Pin 1).

How does the VDRIVE pin function in the AD7475ARMZ?

The VDRIVE pin (Pin 6) sets the logic voltage level for all digital I/O pins (SCLK, CS, SDATA) independently of the analog supply VDD. When VDRIVE = 3 V, the AD7475ARMZ interfaces directly with 3 V microcontrollers-even if VDD = 5 V-eliminating level-shifters. Input thresholds are defined as VINH ≥ VDRIVE − 1 V and VINL ≤ 0.4 V; output VOH ≥ VDRIVE − 0.2 V. This separation reduces digital noise coupling into the analog section and simplifies mixed-voltage system design.

What power-saving modes does the AD7475ARMZ support?

The AD7475ARMZ supports three power states: Normal Mode (1.5 mA at 3 V/1 MSPS), Partial Power-Down Mode (450 µA at 100 kSPS), and Full Power-Down Mode (1 µA max). Power-down is controlled via the CS pin sequence-holding CS high for >100 ns after conversion enters partial mode; asserting CS low then high with >1 µs delay activates full shutdown. Recovery time from full shutdown is 20 µs. These modes enable dynamic power scaling in duty-cycled applications like wireless sensor nodes.

Is the AD7475ARMZ pin-compatible with other devices in the AD7475/AD7495 family?

Yes, the AD7475ARMZ is pin-compatible with the AD7495ARMZ in the same MSOP-8 package, differing only in Pin 1 function: AD7475ARMZ uses REF IN, while AD7495ARMZ uses REF OUT. All other pins (VIN, GND, SCLK, SDATA, VDRIVE, CS, VDD) share identical functions and electrical characteristics. This allows hardware reuse across designs requiring either external or internal reference configurations-only the reference decoupling network and Pin 1 routing need revision.