Texas Instruments TLC1550IDWR

Overview

TLC1550IDWR from Texas Instruments is a 10-bit, switched-capacitor successive-approximation analog-to-digital converter (ADC) with parallel 3-state digital interface, 6 µs conversion time, ±1 LSB total unadjusted error, and dual digital supply rails (DGTL VDD1/DGTL VDD2) for noise isolation in DSP/microprocessor data acquisition systems.

For engineers reviewing the TLC1550IDWR datasheet, TLC1550IDWR pinout, TLC1550IDWR application, or TLC1550IDWR equivalent, this page delivers verified electrical parameters, SOIC-24 package mapping, real-world timing behavior, and validated alternative options for industrial data logging, motor control feedback, and embedded sensor interfacing.

Technical Context

The TLC1550IDWR implements a capacitor-based successive-approximation register (SAR) architecture with internal clock (divided-by-2) and optional external CLKIN up to 7.8 MHz. It uses Advanced LinEPIC™ single-poly CMOS process to achieve close capacitor matching for improved linearity.

Its dual-digital-ground (DGTL GND1/DGTL GND2) and split-digital-supply (DGTL VDD1 for logic, DGTL VDD2 for bus drivers) design minimizes digital switching noise coupling into analog sections. Analog inputs are sampled via a 60 pF input capacitance with 1 kΩ typical hold-mode impedance.

Key Specifications

Pinout & Package

Package: SOIC-24 (DW), 7.5 mm × 15.4 mm body, 1.27 mm pitch, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit parallel-output ADC applications.

Compared with TLC1551IDWR, the TLC1550IDWR saves cost and board area when external reference buffering is already present; versus ADS7822U, it provides guaranteed 10-bit parallel throughput and superior noise immunity in mixed-signal industrial environments.

Availability

TLC1550IDWR is available at Aetrix Electronics and suitable for industrial motor control, factory automation data logging, and embedded power supply monitoring requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TLC1550IDWR 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 connectivity technologies, with over 90 years of innovation in precision data converters and industrial-grade ICs.

The TLC1550x family was designed specifically for high-speed, noise-immune data acquisition in industrial microprocessor and DSP systems - emphasizing parallel interface simplicity, supply rail separation, and robust ESD tolerance.

FAQ

What is the maximum external clock frequency supported by the TLC1550IDWR?

The TLC1550IDWR accepts an external clock (CLKIN) up to 7.8 MHz, as specified in the recommended operating conditions. At this frequency, the device maintains its 6 µs conversion time and ±1 LSB total unadjusted error. Operation above 7.8 MHz may cause timing violations or increased error; the internal clock runs at half the CLKIN frequency, so 7.8 MHz input yields a 3.9 MHz internal rate.

Does the TLC1550IDWR require external reference components?

Yes, the TLC1550IDWR requires external connections to REF+ and REF− to define its full-scale range. It does not include an internal reference or reference buffer. For ratiometric operation, REF+ is typically tied to ANLG VDD (4.75–5.5 V), and REF− to analog ground. A precision external reference (e.g., REF5025) can be used for absolute accuracy applications.

Can the TLC1550IDWR operate with a single 5-V supply?

No - the TLC1550IDWR requires three independent supply connections: ANLG VDD (analog), DGTL VDD1 (logic), and DGTL VDD2 (bus drivers). All three must be supplied at 4.75–5.5 V, but they must be decoupled separately. Using a single 5-V rail for all three violates the noise-isolation design and risks degraded AC performance and increased total unadjusted error.

What is the purpose of separate DGTL GND1 and DGTL GND2 pins on the TLC1550IDWR?

DGTL GND1 serves as the return path for low-current logic circuits (e.g., control logic, SAR register), while DGTL GND2 returns high-current bus driver outputs (D0–D9). This separation prevents large transient currents from the 3-state outputs from inducing voltage spikes on the logic ground plane - a key factor in maintaining ±1 LSB accuracy under heavy bus loading conditions.

Is the TLC1550IDWR pin-compatible with the TLC1551IDWR?

Yes, the TLC1550IDWR and TLC1551IDWR share identical SOIC-24 pinouts, timing specifications, and electrical characteristics. The only functional difference is that the TLC1551IDWR integrates a reference buffer on-chip, while the TLC1550IDWR requires external buffering. Both parts can be substituted on the same PCB layout without modification.