Analog Devices Inc. AD7476AYRM

Overview

AD7476AYRM from Analog Devices is a 12-bit, 1 MSPS successive-approximation analog-to-digital converter (ADC) in a 6-lead SC70 package, operating from 2.35 V to 5.25 V supply. It delivers 71 dB SNR at 100 kHz input, features no pipeline delay, and uses internal VDD-referenced conversion for 0 V to VDD analog input range-ideal for battery-powered data acquisition in portable medical instruments.

For engineers reviewing the AD7476AYRM datasheet, AD7476AYRM pinout, AD7476AYRM application, or AD7476AYRM equivalent, this page provides verified technical context, real-world timing behavior, SC70 package constraints, and validated alternatives for low-power, high-speed single-channel sampling in space-constrained embedded systems.

Technical Context

The AD7476AYRM implements a standard successive-approximation register (SAR) architecture with a track-and-hold amplifier supporting >13 MHz full-power bandwidth. Conversion is initiated on the falling edge of CS, and data is clocked out MSB-first on SDATA synchronized to SCLK falling edges.

It uses VDD as its reference source, eliminating external reference components and enabling rail-to-rail input range (0 V to VDD). The serial interface is SPI/QSPI/MICROWIRE/DSP-compatible, requiring 16 SCLK cycles per conversion with no latency between sample and result availability.

Key Specifications

Pinout & Package

AD7476AYRM is housed in a 6-lead SC70 package (2.2 mm × 1.35 mm × 0.95 mm), optimized for high-density PCB layouts in portable electronics. Its compact footprint and low thermal impedance (θJA = 340.2°C/W) support thermally constrained designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7476ARMZ, the AD7476AYRM offers guaranteed performance across –40°C to +125°C and tighter parametric consistency over temperature-critical for automotive and industrial deployments. Versus ADS7822U, it delivers 5× higher throughput in 45% less board area but requires more careful power-supply decoupling to maintain 71 dB SNR.

Availability

AD7476AYRM is available at Aetrix Electronics and suitable for battery-powered systems, portable medical instruments, optical sensors, and industrial data loggers requiring stable component supply across automotive and extended-temperature environments.

Supply support for AD7476AYRM 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 AD7476A family was designed to deliver high-speed, low-power SAR conversion in ultra-small packages for space- and energy-constrained portable and automotive applications-prioritizing integration, thermal efficiency, and production robustness.

FAQ

What is the maximum sampling rate supported by the AD7476AYRM?

The AD7476AYRM supports a maximum throughput rate of 1 MSPS, achieved with a 20 MHz serial clock (SCLK) and 16 SCLK cycles per conversion. This yields a minimum conversion time of 800 ns. At lower SCLK frequencies, throughput scales linearly-for example, 10 MHz SCLK delivers 500 kSPS-making the AD7476AYRM adaptable to power-constrained or noise-sensitive designs where reduced clock speed improves SNR.

Does the AD7476AYRM require an external voltage reference?

No, the AD7476AYRM uses an internal reference derived from the VDD supply, enabling a full-scale analog input range of 0 V to VDD. This eliminates the need for external reference ICs or resistive dividers, simplifying design and reducing BOM cost. However, VDD must be well-regulated and decoupled-especially at high throughput-since reference noise directly impacts SNR and THD performance.

How does the AD7476AYRM handle power-down mode?

The AD7476AYRM enters full power-down mode when CS remains high and SCLK is inactive, drawing ≤1 µA (typically 50 nA). Recovery time from power-down is ≤1 µs, allowing rapid reactivation for burst-mode sampling. In dynamic power-down (e.g., during idle SCLK periods), current drops to 0.6 mA typical at 5 V, balancing wake-up latency and average power savings in intermittent acquisition systems.

What are the key layout considerations for the AD7476AYRM SC70 package?

Due to its 6-lead SC70 footprint and high analog performance, the AD7476AYRM requires strict layout discipline: separate analog and digital ground planes tied at a single point near VDD/GND pins; 100 nF ceramic decoupling capacitor placed <1 mm from VDD; VIN routed away from digital traces; and SDATA/SCLK traces length-matched and shielded if routing near noise sources. Thermal vias under the exposed pad (if present in variant) are recommended for thermal relief.

Is the AD7476AYRM pin-compatible with other members of the AD7476A/AD7477A/AD7478A family?

Yes-the AD7476AYRM shares identical 6-lead SC70 pinout and serial interface timing with AD7477AYRM and AD7478AYRM. All three variants use the same CS/SCLK/SDATA/VIN/GND/VDD arrangement and 16-bit frame format (4 leading zeros + data + trailing zeros). This allows hardware reuse across 12-/10-/8-bit resolutions, though firmware must adjust bit extraction and timing based on selected resolution.