Texas Instruments ADS7955SRGER

Overview

ADS7955SRGER from Texas Instruments is a 10-bit, 8-channel, 1-MSPS SAR analog-to-digital converter with serial interface, integrated programmable gain amplifier (PGA) input stage, dual software-selectable unipolar input ranges (0 to VREF and 0 to 2×VREF), two per-channel programmable alarm thresholds, and four GPIOs - designed for high-speed industrial data acquisition in PLC/IPC and digital power supply monitoring.

For engineers reviewing the ADS7955SRGER datasheet, ADS7955SRGER pinout, ADS7955SRGER application, or ADS7955SRGER equivalent, key selection criteria include its 1-MHz sampling rate, zero-latency conversion architecture, 20-MHz SPI-compatible serial interface, 2.7–5.25-V analog supply range, and TSSOP-30 package compatibility across the ADS79xx family.

Technical Context

The ADS7955SRGER implements a capacitor-based SAR ADC with inherent sample-and-hold, accepting analog inputs via an 8-channel single-ended multiplexer with MXO output and AINP/AINM differential reference path. It supports both auto-sequencing and manual channel selection modes, with conversion triggered on the falling edge of CS.

Its serial interface uses CS (active-low), SCLK, SDI, and SDO for register configuration and data readout; GPIO0–GPIO3 are individually configurable as inputs/outputs, with GPIO2 serving as Range select (0 = 0–VREF, 1 = 0–2×VREF) and GPIO3 as active-low PD control - enabling flexible system-level integration without external logic.

Key Specifications

Pinout & Package

The ADS7955SRGER is housed in a 30-pin TSSOP package (7.80 mm × 4.40 mm) with exposed thermal pad. All pins are electrically validated per TI SLAS605C Rev C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7955SRGER, ADS7953SRGER trades channel count for resolution headroom in metrology-critical roles, while ADS7957SRGER preserves resolution and adds flexibility for scalable sensor arrays - both maintain identical power, timing, and software compatibility.

Availability

ADS7955SRGER is available at Aetrix Electronics and suitable for PLC/IPC, digital power supply monitoring, and optical line card health management requiring stable component supply, long-term manufacturability, and consistent parametric performance across production lots.

Supply support for ADS7955SRGER 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 and embedded processing technologies, with leadership in precision data converters, power management, and industrial interface solutions.

The ADS79xx product line was engineered specifically for high-speed, multichannel industrial data acquisition - emphasizing zero-latency conversion, flexible alarm handling, and pin-compatible scalability across resolution and channel count variants.

FAQ

What is the maximum sampling rate supported by the ADS7955SRGER?

The ADS7955SRGER supports a maximum sampling rate of 1 MSPS (1 million samples per second). This rate is achievable under recommended operating conditions, including 20-MHz SCLK and proper decoupling. At this speed, the device delivers zero-latency conversion with full 10-bit resolution, making it suitable for demanding real-time control loops and transient capture in industrial systems. The ADS7955SRGER maintains specified INL and SNR performance up to its rated 1-MSPS throughput.

Does the ADS7955SRGER require an external reference voltage?

Yes, the ADS7955SRGER requires an external reference voltage applied to the REFP pin, with REFM tied to analog ground. The device supports two software-selectable input ranges: 0 to VREF and 0 to 2×VREF. A precision reference such as the REF5025 (2.5-V ±0.1% initial accuracy) is recommended to achieve specified total unadjusted error (TUE) of ±1.5 LSB. Internal reference is not provided - all accuracy specifications assume a stable, low-noise external source.

How many GPIOs does the ADS7955SRGER provide, and what are their functions?

The ADS7955SRGER provides four GPIOs (GPIO0–GPIO3) in its 30-pin TSSOP package. GPIO2 serves as Range select (logic high enables 0–2×VREF input range), GPIO3 is an active-low power-down input, and GPIO0/GPIO1 function as programmable alarm outputs (high-alarm and low-alarm, respectively). All GPIOs are individually configurable via internal registers and retain state during conversion cycles - enabling autonomous system-level event handling without host intervention.

Is the ADS7955SRGER pin-compatible with other devices in the ADS79xx family?

Yes, the ADS7955SRGER is fully pin-compatible with all 30-pin TSSOP variants in the ADS79xx family, including ADS7950–ADS7953 (12-bit), ADS7954–ADS7957 (10-bit), and ADS7958–ADS7959 (8-bit). Identical pin assignments for power, interface, analog inputs, and GPIOs allow hardware reuse across resolution and channel-count variants - simplifying design iteration, qualification, and inventory management while preserving layout and firmware compatibility.

What is the power consumption of the ADS7955SRGER at full speed?

The ADS7955SRGER consumes 14.5 mW typical power at 1 MSPS when operated with +VA = 5 V and +VBD = 3 V. This includes analog and digital supply currents under full-load conversion conditions. In power-down mode (GPIO3 low), supply current drops to 1 μA, enabling significant energy savings during idle periods. The device's separate analog (+VA/AGND) and digital (+VBD/BDGND) supplies allow independent rail optimization to further reduce system-level power dissipation.