Analog Devices Inc. AD7812YR

Overview

AD7812YR from Analog Devices is a 10-bit, 8-channel sampling ADC with successive approximation architecture, onboard track-and-hold and 2.5 V ±2.5% internal reference, operating from 2.7 V to 5.5 V supply and delivering 350 kSPS throughput. It supports single-ended or pseudo-differential input configurations and is qualified for automotive applications.

For engineers reviewing the AD7812YR datasheet, AD7812YR pinout, AD7812YR application, or AD7812YR equivalent, this page provides verified technical context, validated pin functions, confirmed dynamic/DC specifications, real-world use scenarios, and two rigorously cross-checked alternative parts for industrial sensor acquisition, motor control feedback, and embedded data logging systems.

Technical Context

The AD7812YR implements a charge redistribution DAC-based successive approximation converter with integrated track-and-hold amplifier and programmable serial interface (TFS/RFS/SCLK/DIN/DOUT). Its control register enables software-configurable channel selection (CH2–CH0), input mode (single-ended vs. pseudo-differential via DIF/SGL and VIN8/AGND bits), power-down state (PD1/PD0), and external reference enable (EXTREF).

It features hardware- and software-initiated conversion start (CONVST edge-triggered or CONVST bit in control register), automatic power-down between conversions, and dual-device bus sharing via A0 address pin and package address bit. Channel-to-channel isolation is –80 dB at 20 kHz, and THD is –66 dB max with 30 kHz input.

Key Specifications

Pinout & Package

AD7812YR is housed in a 20-lead Small Outline IC (SOIC) package (R-20A), 7.5 mm × 12.8 mm body, 1.27 mm pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit, multi-channel SAR ADC applications.

Compared with AD7812YRU, AD7812YR offers superior manufacturability and thermal performance in standard SOIC assembly; compared with AD7912BRUZ, it delivers proven channel configurability and lower idle power at the cost of peak sampling rate - making AD7812YR optimal for deterministic, low-power, multi-sensor embedded systems.

Availability

AD7812YR is available at Aetrix Electronics and suitable for motor control feedback, industrial sensor acquisition, and automotive battery monitoring requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD7812YR 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, founded in 1965 and headquartered in Wilmington, MA.

The AD7811/AD7812 product line was designed specifically for cost-sensitive, space-constrained embedded systems requiring flexible channel count, low power, and automotive-grade reliability - targeting industrial automation, automotive subsystems, and portable instrumentation.

FAQ

What is the maximum sampling rate supported by the AD7812YR?

The AD7812YR supports a maximum sampling rate of 350 kSPS, corresponding to a guaranteed conversion time of 2.3 µs. This rate is achievable across the full operating temperature range (–40°C to +105°C) and supply range (2.7 V to 5.5 V), with timing parameters t1 (conversion time) and tPOWER-UP (1.5 µs) ensuring deterministic behavior in real-time control loops. The AD7812YR maintains this throughput regardless of input configuration (single-ended or pseudo-differential).

Does the AD7812YR require an external reference, or can it operate with its internal reference?

The AD7812YR can operate with its internal 2.5 V ±2.5% reference without any external components - CREF must be connected to a 10 nF capacitor for optimal noise performance. When higher accuracy is needed, an external reference (1.2 V to VDD) may be applied to the VREF pin, and the EXTREF bit in the control register must be set to logic 1 to disable the internal reference and reduce current draw by ~1 mA. The AD7812YR does not require external reference for basic operation.

How many analog input channels does the AD7812YR support, and how are they configured?

The AD7812YR supports eight analog input pins (VIN1–VIN8) that can be configured as either eight single-ended inputs referenced to AGND or four independent pseudo-differential pairs (e.g., VIN1+/VIN2–). Configuration is controlled entirely via the 10-bit software-accessible control register - no external jumpers or resistors are needed. The VIN8/AGND and DIF/SGL bits determine topology, while CH2–CH0 select the active channel during conversion.

Can multiple AD7812YR devices share the same serial interface bus?

Yes, two AD7812YR devices (or one AD7812YR and one AD7811YR) can share the same 3-wire serial bus (SCLK, DIN, DOUT) using the A0 package address pin and the A0 bit in the control register. Each device's A0 pin is hardwired high or low, and only the device whose A0 pin matches the A0 bit in the transmitted control byte will respond to subsequent reads or writes - enabling a 12-channel system without additional interface lines or address decoding logic.

What power-saving modes does the AD7812YR offer, and how are they activated?

The AD7812YR offers three power-saving states: normal operation (3.5 mA), partial power-down (350 µA), and full power-down (1 µA). Partial and full modes are selected via PD1/PD0 bits in the control register and can be triggered automatically at the end of each conversion or manually via software. Full power-down disables the internal reference and most circuitry; partial retains reference bias for faster wake-up. Power-down is entered on the falling edge of CONVST when PD bits are set accordingly.