Texas Instruments ADS7950SDBTR

Overview

ADS7950SDBTR from Texas Instruments is a 12-bit, 4-channel, single-ended SAR analog-to-digital converter with 1-MSPS sample rate, zero-latency operation, and 20-MHz serial interface. It features dual input ranges (0 to VREF and 0 to 2×VREF), programmable per-channel alarm thresholds, and operates from 2.7–5.25 V analog supply. It is used in PLC analog input modules for real-time sensor monitoring.

For engineers reviewing the ADS7950SDBTR datasheet, ADS7950SDBTR pinout, ADS7950SDBTR application, or ADS7950SDBTR equivalent, key selection considerations include its 4-channel count, TSSOP-30 package, 12-bit resolution with ±0.99 LSB DNL, GPIO0–GPIO3 configurability (four pins in TSSOP), and support for auto/manual channel sequencing in industrial data acquisition systems.

Technical Context

The ADS7950SDBTR implements a capacitor-based SAR architecture with integrated sample-and-hold, enabling true zero-latency conversion. Its serial interface uses CS (active-low), SCLK, SDI, and SDO signals for microprocessor/DSP interfacing, with sampling triggered on the falling edge of CS.

It supports two software-selectable unipolar input ranges per channel (0 to VREF or 0 to 2×VREF) and includes two independently programmable alarm levels per channel. Four GPIOs (GPIO0–GPIO3) are available in the TSSOP-30 package, with GPIO2 serving as Range select and GPIO3 as active-low power-down control.

Key Specifications

Pinout & Package

The ADS7950SDBTR is housed in a 30-pin TSSOP (DBT) package measuring 7.80 mm × 4.40 mm, with exposed thermal pad for enhanced heat dissipation in continuous-conversion operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7951SDBTR, the ADS7950SDBTR offers identical performance in a lower-channel-count configuration ideal for cost- and space-constrained 4-input designs; versus ADS8684IPWR, it trades resolution and PGA capability for higher throughput and smaller footprint in standard industrial sensing roles.

Availability

ADS7950SDBTR is available at Aetrix Electronics and suitable for PLC analog input modules, optical line card telemetry, and medical patient monitor subsystems requiring stable component supply across multi-year production cycles.

Supply support for ADS7950SDBTR 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 company specializing in analog, embedded processing, and power management technologies, with leadership in precision data converters and industrial interface solutions.

The ADS79xx family-including ADS7950SDBTR-is designed for high-speed, multi-channel data acquisition in programmable logic controllers, industrial automation, and test equipment where pin compatibility, low latency, and flexible alarm functionality are essential.

FAQ

What is the maximum sample rate supported by the ADS7950SDBTR?

The ADS7950SDBTR supports a maximum sample rate of 1 MSPS (1 million samples per second). This is achieved using its 20-MHz serial interface clock and zero-latency SAR architecture. At this rate, the device consumes 14.5 mW with +VA = 5 V and +VBD = 3 V, making it suitable for high-throughput industrial data logging without excessive thermal load. The ADS7950SDBTR maintains full 12-bit accuracy across the entire 1-MSPS range under specified operating conditions.

Does the ADS7950SDBTR require an external reference voltage?

Yes, the ADS7950SDBTR requires an external reference voltage applied to the REFP and REFM pins. It does not include an internal reference. The device supports two input ranges: 0 to VREF and 0 to 2×VREF, selected via GPIO2. A precision reference such as the REF5025 (2.5 V ± 0.1 V) is recommended to achieve specified total unadjusted error (TUE) performance. Reference input resistance is 100 kΩ typical, and proper decoupling (e.g., 10 µF) is required at REFP for stability.

How many GPIOs are available on the ADS7950SDBTR, and what are their functions?

The ADS7950SDBTR provides four GPIOs (GPIO0–GPIO3) in its TSSOP-30 package. GPIO2 serves as the Range select input (high = 0–2×VREF, low = 0–VREF); GPIO3 is the active-low power-down (PD#) control. GPIO0 and GPIO1 are general-purpose I/Os configurable as inputs or outputs via register programming. All four support alarm reporting: GPIO0 = high-alarm output, GPIO1 = low-alarm output, and GPIO2/GPIO3 retain their dedicated control roles.

What package type and pin count does the ADS7950SDBTR use?

The ADS7950SDBTR uses a 30-pin TSSOP package (orderable code DBT), with nominal body dimensions of 7.80 mm × 4.40 mm. This package shares footprint compatibility with other 4- and 8-channel members of the ADS79xx family (e.g., ADS7951SDBTR), enabling scalable design reuse. The pinout includes dedicated analog inputs (CH0–CH3), reference terminals (REFP/REFM), serial interface signals (CS/SCLK/SDI/SDO), and four GPIOs - all validated per TI's SLAS605C datasheet revision C.

Can the ADS7950SDBTR operate with separate analog and digital supply voltages?

Yes, the ADS7950SDBTR supports independent analog and digital supplies: +VA (2.7–5.25 V) powers the ADC core and analog front-end, while +VBD (1.7–5.25 V) powers the digital I/O interface and GPIOs. This separation allows optimization of noise performance - e.g., +VA can be filtered and regulated separately from noisy digital rails. BDGND and AGND must be connected at a single point to prevent ground loops, and layout guidelines recommend star grounding near the device's thermal pad.