Texas Instruments TLC2543CN

Overview

TLC2543CN from Texas Instruments is a 12-bit successive-approximation analog-to-digital converter (ADC) with serial interface, 11-channel analog multiplexer, on-chip sample-and-hold, and built-in self-test modes. It delivers 10 µs conversion time, ±1 LSB linearity error, and operates from 0°C to 70°C. It is used in industrial data acquisition systems requiring precise ratiometric measurement of multiple sensor inputs.

For engineers reviewing the TLC2543CN datasheet, TLC2543CN pinout, TLC2543CN application, or TLC2543CN equivalent, key selection criteria include unipolar/bipolar output configuration, programmable MSB/LSB-first data format, 4.1 MHz max I/O clock rate, power-down capability, and differential reference input architecture for noise-immune scaling.

Technical Context

The TLC2543CN implements a switched-capacitor successive-approximation ADC core synchronized to an external I/O clock. Its 14-channel analog multiplexer selects among 11 external analog inputs or three internal self-test voltages, with automatic sample-and-hold triggered on the fourth falling edge of the I/O clock.

Conversion control is fully serial: an 8-bit input word (4-bit address + 2-bit data length + 1-bit MSB/LSB + 1-bit unipolar/bipolar) is shifted in on rising edges, while previous conversion results are shifted out on DATA OUT on falling edges. EOC transitions low at conversion start and high upon completion and data latching.

Key Specifications

Pinout & Package

Package: 20-pin plastic DIP (N package), through-hole mounting, 0.3-inch width, JEDEC MS-001 compatible.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit serial ADC applications.

Compared with ADS7822U and MCP3208-I/P, the TLC2543CN uniquely combines 11-channel multiplexing, selectable unipolar/bipolar output, three self-test modes, and differential reference inputs - making it optimal for diagnostic-capable, noise-resilient industrial data acquisition where channel count and functional safety matter.

Availability

TLC2543CN is available at Aetrix Electronics and suitable for industrial sensor monitoring, automated test equipment, energy metering interfaces, and environmental data loggers requiring stable component supply across long production lifecycles.

Supply support for TLC2543CN 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 decades of heritage in precision data converters and industrial-grade ICs.

The TLC2543 family was designed specifically for robust, low-pin-count serial ADC applications in harsh industrial environments - emphasizing multiplexed channel flexibility, ratiometric accuracy, and integrated diagnostics.

FAQ

What is the maximum I/O clock frequency supported by the TLC2543CN?

The TLC2543CN supports an I/O clock frequency up to 4.1 MHz under recommended operating conditions (VCC = 4.5 V to 5.5 V). This allows full 12-bit conversion and data transfer within 12 clock cycles, achieving a theoretical throughput of ~340 kSPS when pipelined - though actual system rate is limited by the 10 µs conversion time and inter-conversion setup overhead. The TLC2543CN maintains specified timing margins and linearity performance only within this rated clock range.

Does the TLC2543CN require an external sample-and-hold circuit?

No, the TLC2543CN integrates a complete sample-and-hold function that activates automatically during the I/O cycle - specifically beginning on the fourth falling edge of the I/O clock and concluding after the final falling edge. This eliminates the need for external S/H components, reduces PCB area, and ensures consistent acquisition timing across all 11 analog inputs. The internal capacitor array is optimized for ≤50 Ω source impedance to maintain full 12-bit accuracy.

How does the TLC2543CN handle bipolar analog inputs?

The TLC2543CN supports bipolar operation via its programmable output format bit (D0): when set, it outputs signed binary data referenced to VREF+/2, enabling direct digitization of signals ranging from –VREF+/2 to +VREF+/2. This requires connecting REF– to a stable midpoint voltage (e.g., VREF+/2) rather than ground. The TLC2543CN's differential reference architecture ensures accurate zero-crossing detection and eliminates offset drift caused by supply variations.

What self-test voltages are available on the TLC2543CN and how are they selected?

The TLC2543CN provides three internal self-test voltages: 0 V (address 1100), mid-scale (VREF+/2, address 1011), and full-scale (VREF+, address 1101). These are selected by loading the corresponding 4-bit channel address into the upper nibble of the 8-bit DATA INPUT stream during the I/O cycle. Self-test mode validates ADC functionality, reference integrity, and serial interface timing without requiring external test equipment - critical for field-deployed diagnostics.

Can the TLC2543CN operate with a 3.3 V supply?

No, the TLC2543CN is specified only for VCC = 4.5 V to 5.5 V per its recommended operating conditions. Absolute maximum ratings permit VCC down to –0.5 V, but functional operation below 4.5 V is not guaranteed - internal biasing, reference generation, and digital logic thresholds are calibrated for 5 V nominal operation. Using 3.3 V risks incomplete conversions, invalid EOC signaling, or latch-up. For 3.3 V systems, consider TI's newer 12-bit SPI ADCs like the ADS7822 or ADS8320.