TLC548CD Equivalent & Substitute Parts

Part Overview

The TLC548CD is an 8-bit Analog to Digital Converter (ADC) manufactured by Texas Instruments, designed for single-ended input applications with a 1:1 Sample-and-Hold to ADC ratio. The device features an external reference type and operates across 3V to 6V supply voltages for both analog and digital domains. The TLC548CD is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations.

Substiute Parts

TLC548CD

Texas InstrumentsIn Stock: 2470TLC548CD Datasheet

Current PartRFQ

ADC081S021CIMF/NOPB

Texas InstrumentsIn Stock: 25912ADC081S021CIMF/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The ADC081S021CIMF/NOPB qualifies as a direct substitute for the TLC548CD based on the following core substitution criteria:

Functional Equivalence Parameters:

• Resolution: Both devices are 8-bit ADCs
• Input Configuration: Both support single-ended input with 1 input channel
• Architecture: Both utilize Successive Approximation Register (SAR) architecture
• Data Interface: Both support SPI communication protocol
• Converter Ratio: Both maintain 1:1 Sample-and-Hold to ADC ratio

Electrical Compatibility Parameters:

• Supply Voltage Range: ADC081S021CIMF/NOPB operates at 2.7V ~ 5.25V, which encompasses the TLC548CD operating range of 3V ~ 6V within the 2.7V ~ 5.25V overlap window
• Both devices are ROHS3 compliant and REACH unaffected

Substitution Limitations: The ADC081S021CIMF/NOPB operates at a higher sampling rate (200k vs. 45.5k) and features an internal supply reference rather than external reference. The package differs (SOT-23-6 vs. 8-SOIC), requiring PCB layout modification. Operating temperature range extends to -40°C ~ 85°C, providing broader environmental coverage than the TLC548CD.

Parameter Comparison

Engineering Selection Recommendations

The ADC081S021CIMF/NOPB is the manufacturer-recommended substitute for the obsolete TLC548CD. Selection of this substitute is justified by:

Product Status Alignment: The TLC548CD is obsolete, while the ADC081S021CIMF/NOPB maintains active production status, ensuring long-term availability and supply chain continuity.

Compliance Certification: Both devices maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for equivalent component substitution.

Functional Compatibility: Core ADC functionality remains equivalent across 8-bit resolution, single-ended input, SAR architecture, and SPI interface support. The substitute's enhanced sampling rate (200k vs. 45.5k) provides performance headroom without functional degradation.

Supply Voltage Consideration: Operation within the overlapping voltage range (3V ~ 5.25V) maintains electrical compatibility. The substitute's internal supply reference eliminates the external reference requirement, simplifying circuit design.

Package Transition: The shift from 8-SOIC to SOT-23-6 packaging requires PCB layout redesign. The SOT-23-6 package offers reduced footprint and improved thermal characteristics suitable for modern manufacturing processes.

Frequently Asked Questions (FAQ)

Q: Can the ADC081S021CIMF/NOPB directly replace the TLC548CD without circuit modification?

A: Direct pin-for-pin replacement is not possible due to package differences (8-SOIC vs. SOT-23-6). PCB layout redesign is required. Additionally, the reference implementation differs (external vs. internal supply reference), necessitating circuit schematic review and potential modification to reference circuitry.

Q: What is the impact of the higher sampling rate in the ADC081S021CIMF/NOPB?

A: The 200k sampling rate of the substitute exceeds the TLC548CD's 45.5k rate. This provides enhanced temporal resolution and faster conversion capability. Existing firmware and software interfaces designed for the slower sampling rate remain compatible; the faster device simply provides additional performance margin.

Q: Are there supply voltage compatibility issues when substituting?

A: The TLC548CD operates at 3V ~ 6V, while the ADC081S021CIMF/NOPB operates at 2.7V ~ 5.25V. Systems operating at voltages above 5.25V (such as 6V supplies) cannot use the substitute without voltage regulation modification. Systems operating within 3V ~ 5.25V are fully compatible.

Q: What are the implications of the reference type change from external to internal supply?

A: The TLC548CD requires an external reference voltage source, while the ADC081S021CIMF/NOPB uses the supply voltage as reference. This simplifies circuit design by eliminating external reference components but requires verification that supply voltage stability meets ADC accuracy requirements.

Q: Does the extended operating temperature range of the substitute affect compatibility?

A: The ADC081S021CIMF/NOPB operates from -40°C ~ 85°C compared to the TLC548CD's 0°C ~ 70°C. This extended range provides additional environmental flexibility and is fully backward compatible with applications designed for the narrower temperature range.

Q: Is the SOT-23-6 package suitable for high-volume production?

A: SOT-23-6 is a standard surface-mount package widely supported by automated assembly equipment. It offers improved thermal performance and reduced board space compared to 8-SOIC, making it suitable for modern manufacturing processes and high-volume production environments.