Analog Devices Inc. AD7475BR

Overview

AD7475BR from Analog Devices is a 12-bit, single-supply successive-approximation ADC with 1 MSPS throughput, 68 dB SINAD at 300 kHz, ±1 LSB INL (B-grade), and operation from 2.7 V to 5.25 V. It features an external 2.5 V reference input, no pipeline delay, and SPI-/QSPI-/MICROWIRE-compatible serial interface - used in portable medical instruments for high-fidelity analog signal digitization.

For engineers reviewing the AD7475BR datasheet, AD7475BR pinout, AD7475BR application, or AD7475BR equivalent, this page delivers verified electrical specs, package mapping to 8-lead MSOP, functional pin roles, real-world use cases in battery-powered instrumentation, and two validated alternative parts with documented technical and application differences.

Technical Context

The AD7475BR implements a capacitive DAC-based successive-approximation architecture with track-and-hold acquisition time ≤325 ns (full-scale step) and aperture jitter of 50 ps. Conversion is initiated on the falling edge of CS and completed in exactly 16 SCLK cycles - eliminating pipeline latency and enabling deterministic timing control in real-time sampling systems.

It supports independent logic-level interfacing via VDRIVE (2.7 V–5.25 V), allowing direct connection to 3 V or 5 V processors regardless of VDD. Power management includes three modes: normal (1.5 mA @ 3 V/1 MSPS), partial power-down (100 µA static), and full shutdown (1 µA), with 800 ns max conversion time at 20 MHz SCLK.

Key Specifications

Pinout & Package

AD7475BR is housed in an 8-lead MSOP package (3.0 mm × 3.0 mm, 0.65 mm pitch), RoHS-compliant, with exposed pad for thermal enhancement. Pin 1 is REF IN; pin 3 is GND (analog ground reference); pin 6 is VDRIVE (independent logic supply); pin 7 is CS (active-low conversion trigger and data framing).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7476BR and ADS7822U, the AD7475BR uniquely balances 1 MSPS speed, sub-5 mW power, external reference flexibility, and VDRIVE-enabled mixed-voltage interfacing - making it the preferred choice for portable medical and optical sensing designs requiring verified 12-bit fidelity within tight thermal and energy budgets.

Availability

AD7475BR is available at Aetrix Electronics and suitable for battery-powered systems, portable medical instruments, and optical sensor interfaces requiring stable component supply across extended production lifecycles.

Supply support for AD7475BR 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, headquartered in Norwood, MA, with design centers worldwide.

The AD7475BR belongs to Analog Devices' precision SAR ADC product line, engineered specifically for portable, low-power, high-fidelity data acquisition in medical, instrumentation, and sensor interface applications.

FAQ

What is the maximum sampling rate supported by the AD7475BR?

The AD7475BR supports a maximum throughput rate of 1 MSPS, achieved with a 20 MHz serial clock (SCLK). At this rate, conversion time is fixed at 800 ns (16 SCLK cycles), and the device maintains full 12-bit performance including 68 dB SINAD at 300 kHz input frequency. Lower SCLK frequencies reduce throughput proportionally but retain all AC/DC specifications.

Does the AD7475BR include an internal voltage reference?

No, the AD7475BR does not include an internal voltage reference. It requires an external 2.5 V ±1% reference applied to the REF IN pin, with a minimum 0.1 µF decoupling capacitor. This contrasts with the pin-compatible AD7495, which integrates a 2.5 V reference on-chip and provides it at the REF OUT pin.

Can the AD7475BR interface directly with a 3 V microcontroller while operating from a 5 V supply?

Yes, the AD7475BR supports mixed-voltage interfacing via its dedicated VDRIVE pin. When VDRIVE = 3 V and VDD = 5 V, the digital I/O thresholds (e.g., VINH = VDRIVE − 1 V = 2 V) align with 3 V logic levels, enabling direct connection to 3 V MCUs without level shifters - a key feature confirmed in the AD7475BR datasheet Rev. D, Table 1 and Functional Block Diagram.

What power-saving modes does the AD7475BR offer, and how much current do they draw?

The AD7475BR offers three power states: normal mode (1.5 mA @ 3 V/1 MSPS), partial power-down (100 µA static), and full power-down (1 µA max). Full shutdown disables the reference buffer, T/H amplifier, and digital logic - verified in Rev. D datasheet, Page 4 (Table 1, "Full Power-Down Mode") and Page 17 ("Full Power-Down Mode" section).

Is the AD7475BR pin-compatible with other devices in the AD7475/AD7495 family?

Yes, the AD7475BR shares identical 8-lead MSOP/SOIC pinout with AD7475AR, AD7475ARMZ, AD7495BR, and AD7495ARMZ. Pin functions (e.g., REF IN on Pin 1 for AD7475 variants vs. REF OUT on Pin 1 for AD7495 variants) differ between families, but mechanical footprint and solder pad layout are fully interchangeable - confirmed in Figures 5 and 6 of Rev. D datasheet.