Texas Instruments ADS7841EB

Overview

ADS7841EB from Texas Instruments is a 12-bit, 4-channel SAR analog-to-digital converter with synchronous serial interface, ±1 LSB INL, 200 kHz max throughput at +5 V, and SSOP-16 package. It supports single-ended or differential inputs, operates from 2.7 V to 5 V, and targets battery-powered data acquisition in portable measurement equipment.

For engineers reviewing the ADS7841EB datasheet, ADS7841EB pinout, ADS7841EB application, or ADS7841EB equivalent, key selection criteria include guaranteed ±1 LSB integral linearity over –40°C to +85°C, programmable 8/12-bit resolution via MODE pin or control byte, and low-power shutdown mode consuming <15 µW.

Technical Context

The ADS7841EB implements a capacitive redistribution SAR architecture with integrated sample-and-hold, enabling true simultaneous sampling across four analog input channels (CH0–CH3) referenced to COM. Its conversion timing is clocked externally via DCLK, supporting 15-, 16-, or 24-clock cycles per conversion depending on resolution and interface optimization.

Digital control is delivered through an 8-bit serial control byte (S-A2-A1-A0-MODE-SGL/DIF-PD1-PD0) shifted in on DIN, with conversion results output on DOUT in straight binary format. The MODE pin overrides the MODE bit for fixed 12-bit operation, and SHDN enables hardware-triggered sub-15 µW shutdown independent of serial control.

Key Specifications

Pinout & Package

ADS7841EB is housed in a 16-pin SSOP (Shrink Small Outline Package) with 0.65 mm pitch, JEDEC MO-153 compliant, package drawing DBQ, footprint code 322. Thermal resistance θ_JA = 150°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7841P and MAX1247, the ADS7841EB delivers superior linearity (±1 LSB), higher throughput (200 kSPS), and hardware-configurable resolution - making it optimal for new designs requiring accuracy, speed, and supply flexibility in space-constrained SSOP layouts.

Availability

ADS7841EB is available at Aetrix Electronics and suitable for portable data loggers, handheld test instruments, and industrial process controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADS7841EB 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 high-reliability ICs, with decades of leadership in precision data converters and industrial-grade components.

The ADS7841EB belongs to TI's precision SAR ADC product line, engineered for low-power, multi-channel digitization in portable and harsh-environment applications - emphasizing linearity, temperature stability, and serial interface simplicity.

FAQ

What is the guaranteed integral linearity error for ADS7841EB over its full operating temperature range?

The ADS7841EB guarantees ±1 LSB maximum integral linearity error (INL) over the –40°C to +85°C temperature range, as specified in the SBAS084B datasheet Absolute Maximum Ratings table. This tighter INL grade distinguishes it from the ADS7841E (±2 LSB) and ensures consistent accuracy in field-deployed instrumentation without recalibration. The ADS7841EB achieves this via enhanced trimming and screening during final test.

Can ADS7841EB operate with a 2.7 V supply and still achieve full 12-bit performance?

Yes, ADS7841EB is fully specified at +2.7 V supply: it maintains 12-bit resolution, ±1 LSB INL, and 125 kHz throughput with VREF = +2.5 V. Electrical Characteristics tables confirm no degradation in DNL, offset, or gain error at minimum supply. However, maximum throughput drops from 200 kHz (at +5 V) to 125 kHz due to internal timing constraints - verified in the +2.7 V Electrical Characteristics section of SBAS084B.

How does the MODE pin affect ADS7841EB resolution control compared to the MODE bit in the control byte?

When the MODE pin is held LOW, ADS7841EB always performs 12-bit conversions regardless of the MODE bit value in the serial control byte - providing hardware-enforced resolution. When MODE is HIGH, the MODE bit determines resolution: LOW = 12-bit, HIGH = 8-bit. This dual-control scheme allows either fixed-precision operation (pin-strapped) or dynamic resolution switching (software-controlled), both supported in ADS7841EB's design.

What is the purpose of the COM pin on ADS7841EB, and how should it be connected?

The COM pin on ADS7841EB serves as the common-mode reference for single-ended analog inputs (CH0–CH3). In single-ended mode, it sets the zero-code voltage - e.g., connecting COM to ground yields a 0 V to VREF input range. It may also be biased to a non-zero voltage (e.g., 0.5 V) to shift the input window. COM must never float; incorrect connection causes code errors and violates absolute input voltage limits per the datasheet's "Analog Inputs" section.

Does ADS7841EB support true differential input pairs, and which channel combinations are valid?

Yes, ADS7841EB supports true differential inputs using any two of CH0–CH3 as +IN and –IN, controlled by the SGL/DIF bit and A2–A0 address bits. Valid differential pairs are CH0–CH1, CH0–CH2, CH0–CH3, CH1–CH2, CH1–CH3, and CH2–CH3 - all defined in Table II of SBAS084B. The device measures the voltage difference (CHx – CHy), rejecting common-mode signals up to 1.25 V on the –IN input, as confirmed in the "Analog Input" theory-of-operation section.