Texas Instruments ADS7817EB/2K5

Overview

ADS7817EB/2K5 from Texas Instruments is a 12-bit, 200kHz SAR analog-to-digital converter with fully differential high-impedance inputs, 2.3mW power consumption at full rate, ±1 LSB integral linearity (B-grade), and MSOP-8 package. It operates from a single +5V supply, accepts external reference voltages from 100mV to 2.5V, and delivers binary two's complement serial output via a 3-wire interface-ideal for transducer interfacing in battery-powered remote data acquisition systems.

For engineers reviewing the ADS7817EB/2K5 datasheet, ADS7817EB/2K5 pinout, ADS7817EB/2K5 application, or ADS7817EB/2K5 equivalent, key selection considerations include its micro-power shutdown current (≤3µA), AC common-mode rejection (>80dB), true differential input architecture, and compatibility with low-noise isolated signal chains in industrial sensing and motor control.

Technical Context

The ADS7817EB/2K5 implements a capacitive redistribution successive approximation register (SAR) architecture fabricated in 0.6µm CMOS, enabling 12-bit resolution with no missing codes across –40°C to +85°C. Its analog front-end features matched +In/–In inputs with 15pF capacitance and ±1µA leakage, supporting both single-ended and fully differential configurations with bipolar input range up to ±VREF.

Digital operation relies on a synchronous 3-wire serial interface: CS/SHDN controls conversion initiation and power-down mode, DCLOCK synchronizes bit transfer on falling edges, and DOUT outputs 12-bit MSB-first data after one null bit-enabling direct connection to microcontrollers without FIFO buffering or pipeline latency.

Key Specifications

Pinout & Package

ADS7817EB/2K5 is housed in an MSOP-8 package (3.0mm × 4.9mm, 0.65mm pitch), optimized for space-constrained PCB layouts in portable instrumentation and modular sensor nodes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7817EB/2K5, ADS7816EB/2K5 trades half the sampling rate for lower active power and identical form factor, while ADS8325IBDGST provides 4 extra bits of resolution at the cost of no shutdown capability and incompatible pinout-making ADS7817EB/2K5 optimal for speed-constrained, battery-operated differential sensing.

Availability

ADS7817EB/2K5 is available at Aetrix Electronics and suitable for transducer interface, battery-powered remote sensing, isolated data acquisition, AC motor control feedback, and industrial process monitoring requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADS7817EB/2K5 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision data converters and industrial-grade IC design.

The ADS7817EB/2K5 belongs to TI's legacy precision SAR ADC product line, engineered specifically for low-power, high-fidelity analog signal digitization in resource-constrained embedded systems-from handheld test equipment to distributed sensor networks.

FAQ

What is the maximum sampling rate supported by the ADS7817EB/2K5?

The ADS7817EB/2K5 supports a maximum sampling rate of 200kHz, achieved with a 3.2MHz DCLOCK signal (16× oversampling). At this rate, the device consumes 2.3mW from a +5V supply and maintains 12-bit resolution with no missing codes. Lower rates reduce power linearly-e.g., 12.5kHz sampling draws only 40µA quiescent current-making ADS7817EB/2K5 adaptable to both high-speed diagnostics and ultra-low-power wake-on-event sensing.

Does the ADS7817EB/2K5 require an external reference voltage?

Yes, the ADS7817EB/2K5 requires an external reference voltage applied to the VREF pin. It accepts any stable voltage from 100mV to 2.5V, which directly defines the full-scale input range (±VREF for differential mode). The reference current varies with output code and sample rate-typically 1.3µA at 12.5kHz and up to 25µA at 200kHz for full-scale codes-so the reference source must be low-noise and capable of driving 15pF capacitance with minimal droop.

What package type is used for the ADS7817EB/2K5?

The ADS7817EB/2K5 is packaged in an MSOP-8 (Mini Small Outline Package) with 3.0mm × 4.9mm body dimensions and 0.65mm lead pitch. This surface-mount package provides thermal and electrical performance equivalent to SOIC-8 but occupies ~50% less PCB area-ideal for compact sensor modules, portable medical devices, and space-limited industrial controllers where the ADS7817EB/2K5 delivers precision A/D conversion without layout compromise.

How does the ADS7817EB/2K5 handle power-down functionality?

The ADS7817EB/2K5 enters full power-down mode when the CS/SHDN pin is driven HIGH, reducing supply current to ≤3µA across –40°C to +85°C. In this state, both analog and digital sections are disabled-no conversions occur, and DOUT goes high-impedance. Returning CS/SHDN LOW initiates a new conversion cycle. This feature enables aggressive duty cycling: for example, a system sampling once per second spends >99.9% of time in shutdown, extending battery life significantly compared to always-on ADCs.

Can the ADS7817EB/2K5 interface directly with a microcontroller SPI port?

Yes, the ADS7817EB/2K5 interfaces directly with standard microcontroller SPI peripherals using its 3-wire serial protocol: CS/SHDN acts as chip select, DCLOCK as SCLK, and DOUT as MOSI (master-out-slave-in). It outputs 12-bit two's complement data MSB-first after one null bit, with timing compliant to common SPI modes. No level-shifting is needed for 5V-tolerant MCUs, and the tri-state DOUT allows sharing the bus with other SPI devices-simplifying firmware integration in systems using ADS7817EB/2K5 for sensor data acquisition.