TLC545CN

Analog To Digital Converters (ADC) Overview

The TLC545CN is an 8-bit successive-approximation analog-to-digital converter (ADC) manufactured by Texas Instruments. It integrates a 20-channel analog multiplexer, sample-and-hold circuit, and serial interface logic within a single CMOS chip. The device operates on a single 5V supply and supports sampling rates up to 76 kSPS with a maximum conversion time of 9 μs. It features a 3-state data output compatible with SPI protocols and includes a built-in self-test mode. The component is housed in a 28-pin plastic dual in-line package (PDIP) and is characterized for operation within the commercial temperature range of 0°C to 70°C.

Analog To Digital Converters (ADC) Feature Summary

• Integrated 20-channel analog multiplexer allowing selection of 19 external inputs or an internal self-test voltage.
• Serial control interface utilizing independent System Clock and I/O Clock signals for flexible microprocessor integration.
• Built-in self-test mode generating a known reference code for verification without external signal sources.
• Software-controllable sample-and-hold function enabling precise timing synchronization for specific acquisition applications.

Analog To Digital Converters (ADC) Applications

• Microprocessor-based data acquisition systems requiring multi-channel input scanning.
• Industrial process control loops involving low-speed sensor monitoring.
• Embedded instrumentation systems utilizing serial communication buses.
• Educational hardware platforms demonstrating ADC principles and multiplexing techniques.

Analog To Digital Converters (ADC) Procurement Notes

Verify component authenticity through authorized distributors or certified secondary market suppliers, as this part number may be subject to obsolescence. Confirm that the received unit matches the 28-PDIP physical dimensions and pinout specifications. Ensure the operating environment remains within the specified 0°C to 70°C range to maintain performance guarantees. Review current availability status prior to finalizing design implementations.

Analog To Digital Converters (ADC) Selection Notes

Select the TLC545CN when an 8-bit resolution and moderate sampling speed are sufficient for the application requirements. Consider this component if the design necessitates an integrated multiplexer to reduce external switching complexity. Evaluate the need for software-controlled sampling versus automatic modes based on system timing constraints. Ensure the host microcontroller can manage the required serial clock frequencies and address shifting sequences.

Analog To Digital Converters (ADC) Part Context

This component belongs to the TLC54x family of CMOS analog-to-digital converters produced by Texas Instruments. It shares architectural similarities with the TLC546, which offers a lower sampling rate, and is compatible with control logic from the TLC540 and TLC1540 families. The 'C' suffix denotes the commercial temperature grade, while the 'N' suffix indicates the plastic DIP packaging format.

Analog To Digital Converters (ADC) Replacement Considerations

The TLC546CN serves as a direct functional substitute within the same package, offering identical pinouts but with reduced maximum sampling rates. Designers must verify that the slower conversion speed of the replacement part does not violate system timing requirements. No other direct pin-compatible replacements are documented in the provided source material.

Analog To Digital Converters (ADC) FAQ

How is the built-in self-test mode activated?

The self-test mode is activated by selecting the internal analog input channel designated as INPUT A19 via the address input pins. This generates a fixed internal voltage for conversion verification.

What is the relationship between the System Clock and I/O Clock?

The System Clock drives the internal conversion circuitry, while the I/O Clock manages data shifting. They operate independently, allowing the System Clock frequency to be up to four times the I/O Clock frequency.

Can the Sample-and-Hold function operate automatically?

Yes, the sample-and-hold circuit can operate automatically during standard conversion cycles. However, it can also be controlled via software to initiate the hold state at a specific point in time for strobing applications.