Analog Devices Inc. AD7823YR-REEL7

Overview

AD7823YR-REEL7 from Analog Devices is an 8-bit successive approximation ADC with 4 µs typical conversion time, pseudo-differential analog input (VIN+, VIN–), and microcontroller-compatible 3-wire serial interface (CONVST, SCLK, DOUT). It operates from a single 2.7 V to 5.5 V supply, features inherent track-and-hold functionality, and is specified over –40°C to +125°C for battery-powered portable instrumentation.

For engineers reviewing the AD7823YR-REEL7 datasheet, AD7823YR-REEL7 pinout, AD7823YR-REEL7 application, or AD7823YR-REEL7 equivalent, key selection considerations include its automatic power-down mode (570 µW at 10 kSPS), ±0.5 LSB relative accuracy, 48 dB SNR at 30 kHz input, VREF range of 1.2 V to VDD, and SOIC-8 package compatibility with space-constrained embedded sensing designs.

Technical Context

The AD7823YR-REEL7 implements a charge redistribution DAC-based SAR architecture with internal oscillator and pseudo-differential sampling. Its CONVST pin serves dual roles: falling edge initiates conversion and places track-and-hold into hold mode; rising edge enables the serial port and controls automatic power-down entry/exit.

Two distinct operating modes are supported: Mode 1 (high-speed, no inter-conversion power-down, 4 µs conversion) and Mode 2 (automatic power-down after each conversion, 6.5 µs effective cycle time including 1.5 µs power-up). The serial interface requires no external logic and supports SPI-like timing with data valid within 5 ns of SCLK rising edge.

Key Specifications

Pinout & Package

AD7823YR-REEL7 is supplied in an 8-lead small outline IC (SOIC) package, 3.9 mm × 4.9 mm body, 1.27 mm lead pitch, RoHS-compliant, tape-and-reel format (REEL7).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit SAR ADC applications.

Compared with AD7810YRZ-REEL7 and ADS7822U, AD7823YR-REEL7 uniquely balances ultra-low power (570 µW @ 10 kSPS), extended temperature operation (–40°C to +125°C), and SOIC-8 footprint-making it the preferred choice for battery-operated industrial sensors where precision beyond 8 bits is unnecessary.

Availability

AD7823YR-REEL7 is available at Aetrix Electronics and suitable for battery-powered test equipment, industrial sensor nodes, and automotive cabin monitoring systems requiring stable component supply across long production lifecycles.

Supply support for AD7823YR-REEL7 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 semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD7823 belongs to Analog Devices' legacy high-speed, low-power SAR ADC product line, designed specifically for portable, battery-constrained applications demanding fast conversion, wide temperature operation, and minimal external components.

FAQ

What is the maximum sampling rate achievable with AD7823YR-REEL7?

The AD7823YR-REEL7 achieves a maximum throughput rate of approximately 133 kSPS in high-speed Mode 1 operation, limited by its 4 µs typical conversion time and serial interface timing. In practice, the actual rate depends on the microcontroller's SCLK speed and software overhead. At 50 kSPS, AD7823YR-REEL7 consumes 2.9 mW; at 10 kSPS with automatic power-down enabled, power drops to 570 µW.

Does AD7823YR-REEL7 require an external reference voltage?

No, AD7823YR-REEL7 does not require an external reference. Its VREF pin accepts 1.2 V to VDD, allowing direct connection to VDD for a 0 V to VDD input range-eliminating external reference components. When VDD = 3.3 V, LSB size is 12.9 mV; when VDD = 5 V, LSB size is 19.5 mV. This simplifies design and reduces BOM cost in many 8-bit applications.

How does the pseudo-differential input of AD7823YR-REEL7 improve measurement accuracy?

The pseudo-differential input (VIN+, VIN–) of AD7823YR-REEL7 enables system-level offset cancellation: applying a known offset (e.g., 0.5 V) to VIN– while measuring VIN+ effectively shifts the input span. This rejects common-mode errors from sensor bias or amplifier offsets. However, VIN– must remain stable within ±0.5 LSB during conversion; otherwise, results become invalid. For true single-ended use, VIN– is tied to AGND.

Can AD7823YR-REEL7 operate reliably at 125°C ambient temperature?

Yes, AD7823YR-REEL7 is fully specified from –40°C to +125°C ambient temperature, including all DC accuracy (±0.5 LSB relative accuracy), dynamic performance (48 dB SNR), and timing parameters. Its SOIC-8 package has θJA = 160°C/W and is qualified for extended temperature operation per Analog Devices' Y-grade testing protocol-making it suitable for under-hood automotive and high-temperature industrial deployments.

What is the function of the CONVST pin in AD7823YR-REEL7 beyond starting conversion?

In AD7823YR-REEL7, the CONVST pin has three critical functions: (1) falling edge initiates conversion and places track-and-hold into hold mode; (2) rising edge enables the serial port (DOUT becomes active) and resets the bit counter; and (3) its logic state at conversion completion determines power-down behavior-low = auto-power-down, high = remain active. This dual-role pin simplifies control sequencing in resource-limited microcontrollers.