Texas Instruments ADS7823E/2K5

Overview

ADS7823E/2K5 from Texas Instruments is a 12-bit successive approximation register (SAR) analog-to-digital converter with I²C interface, designed for low-power remote sensing applications. It delivers 50 kHz sampling rate at high-speed I²C mode (3.4 MHz), supports 2.7 V to 5 V operation, features a 4-word FILO buffer, and uses an external reference input (0.05 V to VDD). It is deployed in isolated data acquisition systems where proximity to signal sources minimizes noise pickup.

For engineers reviewing the ADS7823E/2K5 datasheet, ADS7823E/2K5 pinout, ADS7823E/2K5 application, or ADS7823E/2K5 equivalent, key selection considerations include its MSOP-8 package, I²C bus timing compatibility across standard/fast/high-speed modes, integral linearity error of ±2 LSB, power-down current as low as 2 nA, and hardware address configuration via A0/A1 pins.

Technical Context

The ADS7823E/2K5 implements a capacitive redistribution SAR architecture with integrated sample-and-hold, internally generated asynchronous clocking, and automatic power gating-core circuitry powers down between conversions. Its I²C slave interface supports three operational modes: standard (100 kHz), fast (400 kHz), and high-speed (3.4 MHz), with distinct timing requirements and bus capacitance limits (≤400 pF).

Conversion initiation is triggered by bit-5 of a write-addressed command byte; valid command enables conversion and populates the 4-level FILO buffer in F/S modes, while HS mode disables buffering and stretches SCL to synchronize readout. Reference input range (0.05 V to VDD) directly defines full-scale input (0 to VREF) and LSB weight (e.g., 610 µV at 2.5 V), making accuracy highly dependent on reference stability and noise.

Key Specifications

Pinout & Package

ADS7823E/2K5 is housed in an MSOP-8 (DGK) package, 3.0 mm × 3.0 mm × 1.0 mm body, exposed pad not electrically connected, RoHS-compliant, MSL Level-2-260°C-1 year.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit I²C ADC applications.

Compared with ADS7823E/2K5, ADS7822E/2K5 trades I²C simplicity for higher pin count and SPI dependency, while MCP3221-E/P sacrifices speed and hardware addressing for broader voltage tolerance and lower unit cost-making ADS7823E/2K5 optimal for high-throughput, multi-node, isolated I²C systems.

Availability

ADS7823E/2K5 is available at Aetrix Electronics and suitable for voltage supply monitoring, isolated data acquisition, transducer interface, and battery-operated systems requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for ADS7823E/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 ICs.

The ADS7823E/2K5 belongs to TI's precision SAR ADC product line, engineered specifically for low-power, I²C-connected remote sensing in harsh or space-constrained environments such as industrial automation and portable instrumentation.

FAQ

What is the maximum sampling rate of the ADS7823E/2K5?

The ADS7823E/2K5 achieves a maximum sampling rate of 50 kHz when operating in high-speed I²C mode with SCL = 3.4 MHz. This rate is achievable only when reading one conversion per transaction in HS mode; in standard or fast mode, the effective throughput is limited to 2 kHz or 8 kHz respectively due to I²C timing overhead and FILO buffer behavior. The ADS7823E/2K5 datasheet confirms this value under +2.7 V, VREF = +2.5 V conditions.

Does the ADS7823E/2K5 require an external reference voltage?

Yes, the ADS7823E/2K5 requires an external reference voltage applied to the VREF pin. It accepts inputs from 0.05 V to VDD, and the full-scale analog input range is 0 to VREF. Using an external reference allows precise scaling-for example, a 2.5 V reference yields 610 µV per LSB. The ADS7823E/2K5 does not include an internal reference, and operation is undefined without a valid VREF connection.

How many ADS7823E/2K5 devices can share the same I²C bus?

Up to four ADS7823E/2K5 devices can operate on the same I²C bus, enabled by the A0 and A1 address pins. These pins configure the two least-significant bits of the fixed 7-bit hardware address (10010xx), yielding four unique addresses: 1001000, 1001001, 1001010, and 1001011. Each device must have stable A0/A1 states at power-up; floating pins will result in undefined addressing and bus contention.

What is the purpose of the 4-word FILO buffer in the ADS7823E/2K5?

The 4-word FILO (First-In Last-Out) buffer in the ADS7823E/2K5 stores up to four completed conversion results for sequential readout in standard and fast I²C modes. This decouples the ADC's 50 kHz conversion capability from slower I²C transfer speeds-allowing continuous sampling while the host reads previous results. In high-speed mode, the buffer is bypassed, and conversions are read one-by-one without storage.

What is the power consumption of the ADS7823E/2K5 in power-down mode?

In full power-down mode-with SCL and SDA pulled HIGH-the ADS7823E/2K5 draws only 2 nA to 3 nA typical supply current at +25°C, rising to ≤3000 nA over temperature. This ultra-low state is entered automatically after conversion completion unless actively addressed, and is critical for extending battery life in intermittent-sampling applications. The ADS7823E/2K5 datasheet specifies this value under "Powerdown Mode" in the Electrical Characteristics tables.