Texas Instruments TLC1551IDW

Overview

TLC1551IDW from Texas Instruments is a 10-bit switched-capacitor successive-approximation analog-to-digital converter (ADC) with parallel DSP/microprocessor interface, 6 µs conversion time, ±1 LSB total unadjusted error, and dual digital supply rails (DGTL VDD1/DGTL VDD2) for noise isolation-used in real-time industrial data acquisition systems requiring high-speed sampling and low-noise digital interfacing.

For engineers reviewing the TLC1551IDW datasheet, TLC1551IDW pinout, TLC1551IDW application, or TLC1551IDW equivalent, this page delivers verified technical context, SOIC-24 package mapping, functional pin roles, confirmed timing and accuracy specs, and two validated alternative ADCs for 10-bit parallel-output systems operating from −40°C to 85°C.

Technical Context

The TLC1551IDW implements a switched-capacitor SAR architecture with internal clock generation (7.8 MHz max) and external CLKIN override capability. Its analog section uses separate ANLG VDD/ANLG GND and precision REF+/REF− inputs to support ratiometric conversion, while the digital interface features 10-bit 3-state parallel outputs (D0–D9), chip-select (CS), read (RD), write (WR), and end-of-conversion (EOC) signaling.

It employs Advanced LinEPIC™ single-poly CMOS process with matched capacitors for improved linearity, and separates DGTL GND1/DGTL GND2 and DGTL VDD1/DGTL VDD2 to isolate low-current logic from high-current bus drivers-reducing digital switching noise coupling into analog conversion paths.

Key Specifications

Pinout & Package

Package: SOIC-24 (DW), 15.4 mm × 7.5 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 ADS7822U and TLC1543CN, the TLC1551IDW uniquely delivers 10-bit parallel output with 6 µs conversion, dual digital supplies, and fully configurable external references-making it the only option among the three that supports deterministic, low-latency, memory-mapped acquisition in DSP-centric architectures.

Availability

TLC1551IDW is available at Aetrix Electronics and suitable for industrial motor control, medical diagnostics equipment, automated test instrumentation, and embedded data loggers requiring stable component supply across extended temperature ranges.

Supply support for TLC1551IDW 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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and connectivity technologies for industrial, automotive, and communications markets.

The TLC155x family was designed specifically for high-speed, low-noise data acquisition in real-time embedded systems-emphasizing parallel interfacing, supply-domain isolation, and robust operation from −40°C to 85°C.

FAQ

What is the maximum sampling rate achievable with the TLC1551IDW?

The TLC1551IDW achieves a maximum sustained sampling rate of approximately 166 kSPS, derived from its guaranteed 6 µs conversion time. This assumes minimal overhead between conversions-i.e., WR pulse initiation immediately after EOC assertion-and accounts for data readout timing. The actual system rate may be lower depending on processor bus speed and control signal setup/hold timing compliance.

Does the TLC1551IDW require external reference components?

The TLC1551IDW does not require external reference components to operate-it accepts externally applied REF+ and REF− voltages, but those can be derived from the same ANLG VDD supply (e.g., REF− = 0 V, REF+ = ANLG VDD) for basic unipolar operation. Precision applications may use dedicated voltage references like REF5025 for improved stability and temperature drift performance.

Can the TLC1551IDW operate with a single 5-V supply?

Yes, the TLC1551IDW can operate with a single 5-V supply: ANLG VDD = DGTL VDD1 = DGTL VDD2 = 5 V, and all grounds tied together. However, separating DGTL VDD1 and DGTL VDD2 (even at same voltage) improves noise immunity. The datasheet specifies recommended operation at 4.75–5.5 V for all three supply domains, with no requirement for different voltage levels.

What is the purpose of having two digital ground pins (DGTL GND1 and DGTL GND2) on the TLC1551IDW?

DGTL GND1 serves as the return path for low-current logic circuitry, while DGTL GND2 returns high-current bus driver outputs. This physical separation prevents large transient currents from the D0–D9 drivers from inducing voltage spikes on the logic ground plane-preserving timing margins and reducing digital noise coupling into sensitive analog sections.

Is the TLC1551IDW pin-compatible with the TLC1550IDW?

Yes, the TLC1551IDW is pin-compatible with the TLC1550IDW in the SOIC-24 (DW) package. Both share identical pinout, electrical interface, and timing behavior. The key difference is specification grade: TLC1551IDW guarantees ±1 LSB total unadjusted error over −40°C to 85°C, whereas TLC1550IDW guarantees ±0.5 LSB under same conditions-making TLC1551IDW the cost-optimized variant for less demanding accuracy requirements.