Texas Instruments TLC3578IDWR

Overview

TLC3578IDWR from Texas Instruments is a 14-bit, 8-channel single-ended SAR analog-to-digital converter (ADC) with SPI/DSP-compatible serial interface, ±10 V bipolar input range, 200-KSPS maximum throughput, and integrated 8× FIFO. It operates from a single 5-V analog supply and 3-/5-V digital supply, and is used in precision data acquisition systems requiring high linearity and low power in industrial instrumentation.

For engineers reviewing the TLC3578IDWR datasheet, TLC3578IDWR pinout, TLC3578IDWR application, or TLC3578IDWR equivalent, key selection considerations include its 14-bit resolution with ±1 LSB INL, hardware-configurable sampling (normal/short/extended), built-in conversion clock (6.5 MHz internal OSC), and TSSOP-24 package compatibility with system-level timing-critical signal conditioning.

Technical Context

The TLC3578IDWR implements a successive approximation register (SAR) architecture with an on-chip analog multiplexer supporting eight single-ended inputs and pseudodifferential operation. Its conversion clock is selectable between internal 6.5-MHz oscillator or external SCLK up to 25 MHz, enabling flexible timing control across host processor interfaces.

It features dual ground domains (AGND/DGND), separate analog/digital supplies (AVDD/DVDD), and configurable sampling modes-normal long (44 SCLK), normal short (12 SCLK), or extended via CSTART pin-allowing precise trade-offs between acquisition time, throughput, and source impedance tolerance.

Key Specifications

Pinout & Package

Package: 24-pin TSSOP (PW), RoHS-compliant, body size 7.8 mm × 4.4 mm, 0.65 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution SAR ADC applications.

Compared with ADS8688IPWR and TLC3578IPW, the TLC3578IDWR offers optimal balance of 14-bit performance, industrial temperature rating, and minimal external component count-making it the preferred choice for ruggedized, cost-efficient data acquisition where 16-bit resolution is unnecessary.

Availability

TLC3578IDWR is available at Aetrix Electronics and suitable for industrial process monitoring, motor drive current sensing, portable power quality analyzers, and test & measurement data loggers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TLC3578IDWR 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 IC design.

The TLC3578IDWR belongs to TI's high-performance SAR ADC product line, engineered specifically for industrial data acquisition systems demanding robustness, accuracy, and low-power operation in harsh electromagnetic environments.

FAQ

What is the maximum sampling rate supported by the TLC3578IDWR?

The TLC3578IDWR achieves a maximum throughput of 200 KSPS under normal long-sampling conditions with fixed-channel operation in conversion mode 00 or 01. This rate assumes optimal timing with internal 6.5-MHz conversion clock or external 25-MHz SCLK. Channel-switching reduces effective rate due to multiplexer settling time, and actual sustained throughput depends on host interface latency and FIFO management. The TLC3578IDWR specification sheet confirms this value across all operating conditions within its −40°C to 85°C temperature range.

Does the TLC3578IDWR require an external reference voltage?

Yes, the TLC3578IDWR requires an external differential reference applied to REFP and REFM pins. It does not include an internal reference. The device is specified for a 4-V reference (REFP = 4 V, REFM = 0 V), and decoupling capacitors-10 µF in parallel with 0.1 µF-must be installed between these pins. Using the recommended reference ensures full-scale range of ±10 V and maintains specified AC performance including SINAD of 79 dB at 20 kHz. The TLC3578IDWR datasheet explicitly states that reference stability directly impacts DC accuracy metrics such as EFS(+) and EO.

Can the TLC3578IDWR operate with a 3.3-V digital supply?

Yes, the TLC3578IDWR supports digital supply voltages from 2.7 V to 5.5 V, making it fully compatible with 3.3-V logic systems. DVDD may be set to 3.3 V while maintaining AVDD at 5 V for optimal analog performance. Digital input thresholds scale accordingly: VIH is 2.1 V min at DVDD = 3 V, and VOL remains below 0.4 V at 0.8-mA load. All timing parameters-including SCLK cycle time and setup/hold margins-are validated down to 2.7 V, ensuring reliable SPI communication in mixed-voltage designs using the TLC3578IDWR.

How does the CSTART pin improve sampling accuracy with high-impedance sources?

The CSTART pin enables asynchronous, user-controlled sampling initiation independent of SCLK timing, allowing precise extension of the acquisition window for sources exceeding 25 Ω output impedance. A low pulse on CSTART starts sampling; its duration directly determines hold time before conversion begins. This bypasses SCLK-limited sampling periods (e.g., 12 or 44 cycles), preventing charge injection errors and settling inaccuracies. For example, driving a 1-kΩ sensor requires >1 µs acquisition-achievable only via CSTART on the TLC3578IDWR, as confirmed in the functional block diagram and terminal description sections of its datasheet.

Is the TLC3578IDWR pin-compatible with other devices in the TLC35xx family?

The TLC3578IDWR shares identical pinout and package (TSSOP-24) with TLC3578IPW and TLC3574IDWR, but is not pin-compatible with TLC2578 variants due to differing analog input counts (8 vs. 4 channels) and associated pin assignments. Specifically, pins A4–A7 are dedicated analog inputs on TLC3578IDWR but are no-connect or repurposed on TLC2574/74 devices. The TLC3578IDWR datasheet's "Terminal Functions" table and top-view package diagrams confirm this mapping, and substitution requires verification of both pin function alignment and firmware register compatibility.