Analog Devices Inc. AD7495BR-REEL

Overview

AD7495BR-REEL from Analog Devices is a 12-bit, 1 MSPS successive-approximation ADC with on-chip 2.5 V reference, single-supply operation (2.7 V to 5.25 V), 68 dB SINAD at 300 kHz input, and SPI-compatible serial interface. It serves as a precision analog front-end digitizer in portable instrumentation requiring low power and high throughput.

For engineers reviewing the AD7495BR-REEL datasheet, AD7495BR-REEL pinout, AD7495BR-REEL application, or AD7495BR-REEL equivalent, key selection criteria include on-board reference availability, 1 µA full shutdown current, VDRIVE logic-level independence, no pipeline delay, and MSOP-8 package compatibility with space-constrained PCB layouts.

Technical Context

The AD7495BR-REEL implements a capacitive DAC-based successive-approximation architecture with track-and-hold acquisition time ≤325 ns for full-scale steps. Its conversion is initiated by CS falling edge and clocked by SCLK, requiring exactly 16 cycles at up to 20 MHz - yielding deterministic 800 ns max conversion time and zero pipeline latency.

It features dual supply domains: VDD powers analog and core logic (2.7–5.25 V), while VDRIVE independently sets I/O voltage (2.7–5.25 V), enabling direct interfacing to 3 V or 5 V microcontrollers without level shifters. The integrated 2.5 V reference (±1% initial accuracy, 50 ppm/°C TC) is buffered on REF OUT and requires ≥100 nF decoupling to GND.

Key Specifications

Pinout & Package

AD7495BR-REEL is housed in an 8-lead MSOP package (3.0 mm × 3.0 mm × 1.1 mm body, 0.65 mm pitch), optimized for high-density PCB layouts in portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7475BRMZ-REEL, AD7495BR-REEL trades slightly higher operational power for significant BOM simplification via integrated reference; compared with ADS7822U, it delivers 4× faster throughput and 3 dB higher SINAD at the cost of higher quiescent current - making it optimal for portable instrumentation demanding both speed and precision.

Availability

AD7495BR-REEL is available at Aetrix Electronics and suitable for portable medical sensors, optical sensor interfaces, industrial data loggers, mobile communication test equipment, and battery-powered instrumentation requiring stable component supply across production lifecycles.

Supply support for AD7495BR-REEL 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 AD7495BR-REEL belongs to Analog Devices' precision SAR ADC product line, designed specifically for battery-powered and space-constrained applications requiring high throughput, low power, and integrated reference functionality without sacrificing DC accuracy or AC performance.

FAQ

What is the reference voltage specification for the AD7495BR-REEL?

The AD7495BR-REEL features an on-chip 2.5 V reference with output voltage specified from 2.4625 V to 2.5375 V (±1.5%), typical temperature coefficient of 50 ppm/°C, and output impedance of 10 Ω. This reference is available on the REF OUT pin and requires a minimum 100 nF ceramic capacitor to GND for stability. The AD7495BR-REEL does not accept external reference inputs - unlike the AD7475 - and relies entirely on this internal source for full-scale scaling.

Does the AD7495BR-REEL support true 1 MSPS continuous conversion?

Yes, the AD7495BR-REEL achieves a guaranteed 1 MSPS throughput rate under specified conditions: VDD = 2.7 V to 5.25 V, fSCLK = 20 MHz, and TA = −40°C to +85°C. Each conversion requires exactly 16 SCLK cycles, resulting in a fixed 800 ns max conversion time. With proper CS timing and ≥100 ns quiet time between conversions, sustained 1 MSPS operation is fully supported - confirmed in Table 2 and Timing Example 1 of the AD7495 datasheet Rev. D.

Can the AD7495BR-REEL interface directly with a 1.8 V microcontroller?

No - the AD7495BR-REEL's VDRIVE pin accepts only 2.7 V to 5.25 V, and its digital inputs require VINH ≥ VDRIVE − 1 V and VINL ≤ 0.4 V. Driving SDATA, SCLK, or CS from a 1.8 V MCU violates the input high voltage specification. To interface with 1.8 V logic, a level-shifting buffer (e.g., TXB0108) must be used on all digital lines, or a compatible 2.7 V–3.6 V MCU should be selected. The AD7495BR-REEL itself cannot operate with VDRIVE below 2.7 V.

What is the meaning of "no pipeline delay" for the AD7495BR-REEL?

"No pipeline delay" means the AD7495BR-REEL is a true successive-approximation register (SAR) ADC with deterministic, single-cycle conversion behavior: sampling is triggered by the CS falling edge, and the 12-bit result is fully available on SDATA after exactly 16 SCLK cycles - with no intermediate or overlapping conversions. Unlike pipelined or sigma-delta ADCs, there is no latency beyond the fixed 800 ns conversion time, enabling precise time-aligned sampling in closed-loop control or synchronized multi-channel acquisition.

How does the VDRIVE pin function in the AD7495BR-REEL?

The VDRIVE pin on the AD7495BR-REEL sets the voltage level for all digital I/O pins (CS, SCLK, SDATA), independent of VDD. When VDRIVE = 3.3 V, the device drives and receives logic signals at 3.3 V levels - even if VDD = 5 V for analog performance. This allows direct connection to 3 V or 5 V host processors without level shifters. VDRIVE must be within 2.7 V to 5.25 V and tied to a stable supply; it is not a regulator but a reference rail for I/O threshold definition.