Analog Devices Inc. AD7811YRU

Overview

AD7811YRU from Analog Devices is a 10-bit, 4-channel, successive-approximation ADC with 2.3 µs conversion time, onboard track-and-hold and 2.5 V ±2.5% internal reference, operating from 2.7 V to 5.5 V supply. It supports single-ended or pseudo-differential input configurations and features DSP/microcontroller-compatible serial interface for embedded data acquisition in industrial sensor interfaces and portable instrumentation.

For engineers reviewing the AD7811YRU datasheet, AD7811YRU pinout, AD7811YRU application, or AD7811YRU equivalent, key selection considerations include its 350 kSPS throughput, ±1 LSB relative accuracy, 16-pin TSSOP package with addressable serial bus sharing, and automotive-qualified operation across –40°C to +105°C.

Technical Context

The AD7811YRU implements a charge redistribution DAC architecture with internal oscillator and comparator-based successive approximation logic. Its serial interface uses separate RFS/TFS framing signals synchronized to SCLK, enabling compatibility with TI C5x/C6x and ADSP-21xx DSP families.

Input channel configuration is fully software-controlled via a 10-bit write-only control register, supporting dynamic reconfiguration of VIN1–VIN4 as four single-ended inputs, three pseudo-differential pairs referenced to VIN4, or two independent pseudo-differential channels (VIN1/VIN2 and VIN3/VIN4). Power-down mode is triggered automatically post-conversion or via PD1/PD0 bits.

Key Specifications

Pinout & Package

AD7811YRU is housed in a 16-lead Thin Shrink Small Outline Package (TSSOP), 4.4 mm × 5.0 mm body size, 0.65 mm lead pitch, thermally enhanced for low θ_JA = 115°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7811YR and AD7910BRMZ, the AD7811YRU uniquely balances ultra-small TSSOP packaging, integrated reference and track/hold, and flexible input configuration-making it optimal for space-constrained, low-component-count industrial and automotive sensing nodes.

Availability

AD7811YRU is available at Aetrix Electronics and suitable for industrial sensor interfaces, portable data loggers, automotive cabin controls, and DSP-based motor feedback systems requiring stable component supply and long-term lifecycle assurance.

Supply support for AD7811YRU 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, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD7811YRU belongs to Analog Devices' precision SAR ADC product line, designed specifically for cost-sensitive, space-constrained embedded systems requiring integrated reference, low power, and flexible channel configuration without sacrificing DC accuracy or AC performance.

FAQ

What is the maximum sampling rate achievable with the AD7811YRU?

The AD7811YRU achieves a guaranteed 350 kSPS throughput, derived from its 2.3 µs conversion time plus minimum inter-conversion timing overhead. At this rate, the device maintains full 10-bit linearity and 58 dB SNR with internal reference. Higher rates are not supported due to internal clock and settling constraints-exceeding 350 kSPS risks missing codes and degraded THD.

Can the AD7811YRU operate with an external reference, and how is it configured?

Yes, the AD7811YRU supports external references from 1.2 V to VDD applied to the VREF pin. To enable external reference mode, the EXTREF bit (bit 0) in the 10-bit control register must be set to logic 1. Doing so powers down the internal 2.5 V reference, reducing supply current by ~1 mA and eliminating its 50 ppm/°C drift contribution.

How does the AD7811YRU handle channel selection and input configuration?

The AD7811YRU uses a 10-bit software-configurable control register to define input topology: DIF/SGL and VIN4/AGND bits select between four single-ended, three pseudo-differential (vs. VIN4), or two independent pseudo-differential (VIN1/VIN2 and VIN3/VIN4) modes. Channel selection is performed via CH1/CH0 bits, with configuration retained until rewritten-enabling dynamic re-mapping during runtime.

Is the AD7811YRU pin-compatible with other members of the AD7811/AD7812 family?

No, the AD7811YRU is not pin-compatible with AD7812 variants (e.g., AD7812YRU), which use a 20-pin TSSOP package. However, it shares identical pin functions and layout symmetry with AD7811YR (SOIC) and AD7811YN (DIP) within the AD7811 family-only package dimensions and thermal pad presence differ. Signal routing remains consistent across AD7811 variants.

What power-saving modes does the AD7811YRU support, and how are they activated?

The AD7811YRU supports three power-saving states: automatic partial power-down (350 µA), automatic full power-down (1 µA), and manual full power-down (1 µA). Activation occurs via PD1/PD0 bits in the control register or implicitly at conversion end based on CONVST pin state. Full power-down disables internal reference and oscillator; partial mode retains reference bias for faster wake-up.