Texas Instruments ADS7822EC/2K5G4

Overview

ADS7822EC/2K5G4 from Texas Instruments is a 12-bit, 200kHz SAR analog-to-digital converter with pseudo-differential input, serial CMOS interface, and microPower operation (0.54mW at 75kHz). It features ±0.75 LSB integral linearity error, operates from 2.7V to 5.25V, and uses an external reference adjustable from 50mV to VCC - ideal for battery-powered remote sensing nodes.

For engineers reviewing the ADS7822EC/2K5G4 datasheet, ADS7822EC/2K5G4 pinout, ADS7822EC/2K5G4 application, or ADS7822EC/2K5G4 equivalent, key selection criteria include guaranteed ±0.75 LSB INL/DNL over –40°C to +85°C, MSOP-8 package compatibility, power-down current ≤3μA, and support for synchronous 3-wire serial data transfer with falling-edge sampling.

Technical Context

The ADS7822EC/2K5G4 implements a capacitive redistribution successive approximation register (SAR) architecture on a 0.6μm CMOS process, integrating sample-and-hold functionality. Its pseudo-differential input accepts +In and –In signals where –In is fixed during conversion and used for remote ground sensing, not resampled mid-cycle.

It requires an external reference (50mV–VCC), external clock (10kHz–3.2MHz), and single supply (2.7V–5.25V). Conversion timing is defined by DCLOCK edges: 1.5–2.0 clock cycles for acquisition, 12 cycles for conversion, and serial output begins after the second falling DCLOCK edge following CS low.

Key Specifications

Pinout & Package

ADS7822EC/2K5G4 is packaged in an MSOP-8 (DGK) footprint measuring 3.0mm × 3.0mm × 1.0mm, compatible with automated SMT assembly and space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822UC/2K5, the ADS7822EC/2K5G4 offers identical electrical performance in a smaller MSOP-8 package with lower active current; compared with ADS8320EB/250, it trades resolution for speed and microPower efficiency - making ADS7822EC/2K5G4 optimal for battery-operated, medium-accuracy, high-throughput sensing.

Availability

ADS7822EC/2K5G4 is available at Aetrix Electronics and suitable for battery-operated systems, remote data acquisition modules, and isolated industrial sensor interfaces requiring stable component supply and long-term manufacturability.

Supply support for ADS7822EC/2K5G4 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, embedded processing, and connectivity technologies with over 50 years of innovation in precision data converters.

The ADS7822 product line was designed for ultra-low-power, high-accuracy analog-to-digital conversion in space- and energy-constrained applications including portable instrumentation and distributed sensor networks.

FAQ

What is the guaranteed integral linearity error for ADS7822EC/2K5G4 across its operating temperature range?

The ADS7822EC/2K5G4 guarantees ±0.75 LSB integral linearity error over the full –40°C to +85°C temperature range, as specified in the Electrical Characteristics table for the 'C' grade variant. This corresponds to <0.018% of full-scale range when using a 2.5V reference, enabling high-accuracy measurements without system-level calibration in industrial environments.

Does ADS7822EC/2K5G4 support true differential input operation?

No, ADS7822EC/2K5G4 implements a pseudo-differential input architecture: the voltage difference between +In and –In is sampled once at conversion start and held, but –In is not resampled during conversion. The –In pin is intended for remote ground sensing (e.g., connecting to a distant ground reference), not for rejecting large common-mode signals like a true differential ADC.

What is the minimum clock frequency required for ADS7822EC/2K5G4 to maintain specified performance?

The ADS7822EC/2K5G4 does not specify a minimum clock frequency for DC accuracy, but its conversion timing requires ≥12 DCLOCK cycles per sample. At 75kHz throughput, the minimum clock frequency is 1.2MHz (16× oversampling). For lower sample rates, clock can be reduced - e.g., 120kHz clock supports 7.5kHz sampling - but leakage effects may degrade performance below ~10kHz clock.

Can ADS7822EC/2K5G4 operate with a 2.0V supply voltage?

Yes, ADS7822EC/2K5G4 is specified to operate down to 2.0V supply voltage per the Absolute Maximum Ratings and Recommended Operating Conditions, though full 200kHz throughput is only guaranteed at 4.75V–5.25V. At 2.0V, maximum sample rate drops to ~7.5kHz, and power consumption falls to 20μA quiescent current - making it viable for ultra-low-voltage energy harvesting systems.

How does the reference voltage affect noise performance in ADS7822EC/2K5G4?

In ADS7822EC/2K5G4, internal noise (33μVrms) translates to larger LSB-equivalent error as reference voltage decreases: with a 2.5V reference, noise contributes ~0.32 LSB peak-to-peak, but with a 50mV reference, it becomes ~16 LSBs. Therefore, lower references require tighter layout control, better bypassing, and low-noise references to maintain effective resolution - the ENOB curve in Figure 11 confirms this trade-off.