Texas Instruments ADS7959SRGER

Overview

ADS7959SRGER from Texas Instruments is an 8-bit, 8-channel, 1-MSPS serial interface SAR ADC with zero latency, programmable input ranges (0 to VREF or 0 to 2×VREF), two per-channel alarm thresholds, and one GPIO. It operates from 2.7–5.25 V analog supply and interfaces gluelessly with microprocessors via CS/SCLK/SDI/SDO in a 24-pin VQFN package - used in digital power supply monitoring and PLC analog input modules.

For engineers reviewing the ADS7959SRGER datasheet, ADS7959SRGER pinout, ADS7959SRGER application, or ADS7959SRGER equivalent, key selection criteria include its 1-MSPS throughput, 8-bit resolution with 20-MHz SPI-compatible interface, single-supply operation down to 2.7 V, low 1 μA power-down current, and support for auto/manual channel sequencing in space-constrained industrial sensing nodes.

Technical Context

The ADS7959SRGER implements a capacitor-based SAR architecture with integrated sample-and-hold, accepting unipolar inputs referenced to REFP/REFM. Its conversion is triggered on the falling edge of CS and synchronized to SCLK, enabling deterministic timing for closed-loop control.

It supports two software-selectable full-scale ranges (0–VREF and 0–2×VREF), independent per-channel high/low alarm registers, and manual or auto-sequenced channel selection - all configurable via its 20-MHz serial interface without external timing components.

Key Specifications

Pinout & Package

The ADS7959SRGER is housed in a 4.00 mm × 4.00 mm, 24-pin VQFN (RGE) package with wettable flanks, optimized for automated optical inspection and thermal performance in dense PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel SAR ADC applications.

Compared with ADS7959SRGER, ADS7951SRGER offers higher resolution in the same package with no layout change, while ADS7953SRHRT provides greater channel density and precision at the cost of increased board area and power - making ADS7959SRGER optimal for cost- and space-sensitive 8-bit monitoring tasks.

Availability

ADS7959SRGER is available at Aetrix Electronics and suitable for digital power supplies, PLC analog input modules, optical line card monitoring, and portable medical instrumentation requiring stable component supply across production lifecycles.

Supply support for ADS7959SRGER 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 interface solutions.

The ADS79xx family was designed specifically for multichannel, medium-speed industrial data acquisition - balancing resolution, speed, integration, and power efficiency in harsh electromagnetic environments.

FAQ

What is the maximum sampling rate supported by the ADS7959SRGER?

The ADS7959SRGER supports a maximum sampling rate of 1 MSPS (1 million samples per second). This rate is achievable under recommended operating conditions with +VA = 5 V and +VBD = 3 V. At this rate, the device maintains specified AC performance including SNR and THD, and the serial interface operates up to 20 MHz to sustain full-throughput data transfer. The ADS7959SRGER achieves this using zero-latency SAR architecture without pipeline delay.

Does the ADS7959SRGER require an external reference voltage?

Yes, the ADS7959SRGER requires an external reference voltage applied to the REFP pin, with REFM tied to AGND. The device supports two input ranges: 0 to VREF and 0 to 2×VREF, selectable via the RANGE GPIO. TI recommends using a precision reference such as the REF5025 (2.5 V ±0.1 V) for optimal accuracy. Internal reference is not provided - all voltage measurements are ratiometric to the applied VREF.

How many GPIOs does the ADS7959SRGER include, and what functions do they support?

The ADS7959SRGER includes one GPIO (GPIO0) in its 24-pin VQFN (RGE) package. Per the datasheet, this pin is programmable as either an active-high alarm output (indicating high/low threshold violation) or a general-purpose digital I/O. Unlike TSSOP variants, the RGE package does not support additional GPIOs. Configuration is performed via the device's serial interface registers, and GPIO0 state is readable and writable in real time.

Can the ADS7959SRGER operate with different analog and I/O supply voltages?

Yes, the ADS7959SRGER supports independent analog and digital I/O supplies: +VA (2.7–5.25 V) powers the ADC core and analog front end, while +VBD (1.7–5.25 V) sets logic thresholds for CS, SCLK, SDI, and SDO. This dual-supply capability enables glueless interfacing with mixed-voltage systems - for example, +VA = 5 V for sensor signal conditioning and +VBD = 1.8 V for direct connection to a low-voltage FPGA or MCU without level shifters.

What package type and dimensions does the ADS7959SRGER use?

The ADS7959SRGER uses a 24-pin VQFN package (RGE variant) with nominal body dimensions of 4.00 mm × 4.00 mm and 0.5-mm lead pitch. It features wettable flanks for reliable solder joint inspection and has thermal pad exposed on the bottom for enhanced heat dissipation. This package is distinct from the 30-pin TSSOP and 32-pin VQFN options used by other members of the ADS79xx family.