Texas Instruments ADS8515IDB

Overview

ADS8515IDB from Texas Instruments is a 16-bit, 250-kSPS successive approximation register (SAR) analog-to-digital converter with ±10 V input range, internal 4.096 V reference, and full parallel 16-bit twos-complement output. It operates from a single +5 V analog supply, supports flexible I/O voltage (1.65–5.25 V), and delivers 90 dB min SNR at 20 kHz for precision industrial data acquisition.

For engineers reviewing the ADS8515IDB datasheet, ADS8515IDB pinout, ADS8515IDB application, or ADS8515IDB equivalent, this page provides verified technical context, real-world timing behavior, package-specific layout guidance, and validated alternative options for high-accuracy bipolar sampling systems.

Technical Context

The ADS8515IDB implements a capacitor-based SAR architecture with integrated sample-and-hold, internal reference buffer, and three-state parallel output drivers. Its control logic uses CS and R/C pins in OR-gated configuration to initiate conversion and enable data readout, with BUSY signaling conversion completion.

It features a fixed ±10 V input range via precision on-chip resistor network (2 kΩ, 7 kΩ, 25.67 kΩ), 2.2 µF external CAP decoupling for CDAC charge delivery, and dual ground separation (AGND1, AGND2, DGND) to minimize digital feedthrough into analog signal path.

Key Specifications

Pinout & Package

ADS8515IDB is housed in a 28-pin SSOP (DB) package with exposed pad for thermal management. Pin spacing is 0.65 mm, body width 5.3 mm, and total footprint 9.7 × 6.4 mm. Layout requires strict analog/digital ground separation and dedicated 2.2 µF tantalum capacitor on CAP pin.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with ADS8515IDB, ADS8517IDB offers 8× higher speed at cost of 80% more power and revised timing margins, while ADS8860IPWR trades parallel simplicity for footprint reduction and serial integration-neither is pin-compatible, but both serve adjacent resolution/speed trade-offs in industrial sensing.

Availability

ADS8515IDB is available at Aetrix Electronics and suitable for industrial process control, medical instrumentation, and high-fidelity data acquisition systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for ADS8515IDB 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-grade ICs.

The ADS8515IDB belongs to TI's precision SAR ADC product line, designed specifically for high-accuracy, medium-speed industrial and medical measurement systems requiring robust ±10 V input handling and minimal external components.

FAQ

What is the maximum sampling rate supported by the ADS8515IDB?

The ADS8515IDB is specified for continuous operation at 250 kSPS over the full industrial temperature range (–40°C to +85°C). Its conversion time is 2 ms and acquisition time is 2 ms, resulting in a minimum cycle time of 4 ms. Exceeding 250 kSPS risks violating timing margins and degrading INL/SNR performance, as confirmed in the Electrical Characteristics table under Throughput Rate.

Does the ADS8515IDB require an external reference voltage?

No, the ADS8515IDB includes an internal 4.096 V reference with ±20 mV initial accuracy and 8 ppm/°C typical drift. It can operate fully self-contained using this reference. An external 3.9–4.2 V reference may be applied to REF (pin 3) to improve full-scale accuracy or reduce drift, but it is not required for basic functionality of the ADS8515IDB.

How is data read from the ADS8515IDB - parallel or serial interface?

The ADS8515IDB provides full 16-bit parallel output in binary twos-complement format on pins D0 (LSB) through D15 (MSB). Data becomes valid when R/C goes high (with CS low), and BUSY going high indicates data readiness. BYTE (pin 23) enables 8-bit byte-mode reads. No serial interface is present - the ADS8515IDB is strictly parallel-output.

What package type and pin count does the ADS8515IDB use?

The ADS8515IDB is packaged in a 28-pin SSOP (Shrink Small Outline Package) with designation DB. It measures 9.7 mm × 6.4 mm with 0.65 mm lead pitch. This package is distinct from the SOIC variant and requires specific land pattern and reflow profile per TI's SSOP-28 guidelines - the "IDB" suffix explicitly denotes this SSOP-28 configuration.

Can the ADS8515IDB interface directly with a 3.3 V microcontroller?

Yes, the ADS8515IDB supports flexible I/O supply (VDIG) from 1.65 V to 5.25 V. When VDIG = 3.3 V, its digital outputs meet 3.3 V logic thresholds (VOH ≥ 2.64 V, VOL ≤ 0.4 V), and inputs accept standard 3.3 V CMOS levels. No level-shifting circuitry is needed, provided AGND1/AGND2/DGND are properly partitioned per the layout guidelines in the ADS8515IDB datasheet.