TLC545IFN Equivalent & Substitute Parts

Part Overview

The TLC545IFN is an 8-bit Analog to Digital Converter (ADC) manufactured by Texas Instruments, designed for data acquisition applications. It features a Successive Approximation Register (SAR) architecture with 20 single-ended inputs, an external/internal reference type, and operates at a sampling rate of 76 kHz. The device is packaged in a 28-PLCC (11.51x11.51) surface mount configuration and is compliant with ROHS3 and REACH standards.

The TLC545IFN is classified as an obsolete product. Finding equivalent or substitute parts is necessary to support legacy system maintenance, design updates, or when original inventory becomes unavailable.

Substiute Parts

TLC545IFN

Texas InstrumentsIn Stock: 776TLC545IFN Datasheet

Current PartRFQ

ADS7961SRHBT

Texas InstrumentsIn Stock: 825ADS7961SRHBT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TLC545IFN is determined by the following core electrical and mechanical parameters:

Resolution and Architecture: Both the main part and substitute must maintain 8-bit resolution with SAR architecture to ensure equivalent analog-to-digital conversion performance.

Data Interface: SPI compatibility is required for direct integration into existing system designs without firmware modification.

Input Configuration: Single-ended input type must be preserved for signal acquisition compatibility.

Supply Voltage Compatibility: The substitute must operate within or encompass the 5V supply voltage range of the original design. Devices with wider supply voltage ranges (2.7V ~ 5.25V) are acceptable as they maintain backward compatibility.

Operating Temperature Range: The substitute must support the minimum operating temperature of -40°C. Extended upper temperature ranges are acceptable.

Package and Mounting: Surface mount technology is required. Package form factor differences are acceptable if the substitute is available and functionally equivalent, though physical board layout modifications may be necessary.

Compliance and Certifications: ROHS3 compliance and REACH unaffected status ensure regulatory alignment with the original part.

Parameter Comparison

Engineering Selection Recommendations

The ADS7961SRHBT is a functionally equivalent substitute for the TLC545IFN based on the following criteria:

Both devices share identical 8-bit resolution, SAR architecture, and SPI data interface, ensuring direct functional compatibility at the signal acquisition level.

The ADS7961SRHBT is an active product with current manufacturing support, addressing the obsolescence status of the TLC545IFN. This ensures long-term availability and supply chain stability.

Both parts maintain ROHS3 compliance and REACH unaffected status, preserving regulatory alignment with the original design.

The ADS7961SRHBT operates across a wider supply voltage range (2.7V ~ 5.25V) compared to the fixed 5V requirement of the TLC545IFN, providing greater design flexibility while maintaining full backward compatibility with existing 5V systems.

The extended operating temperature range of the ADS7961SRHBT (-40°C ~ 125°C) exceeds the original specification, supporting applications with more demanding thermal requirements.

The ADS7961SRHBT features a higher sampling rate (1M vs. 76k), providing performance headroom for applications requiring faster conversion speeds.

Design considerations include the reduction in input channels from 20 to 16 and the change in package form factor from 28-PLCC to 32-VQFN. These differences require evaluation against specific application requirements and may necessitate board layout modifications.

Frequently Asked Questions (FAQ)

Q: Can the ADS7961SRHBT directly replace the TLC545IFN without firmware changes?

A: The ADS7961SRHBT maintains SPI interface compatibility and identical 8-bit SAR architecture, allowing direct firmware compatibility. However, the reduction from 20 to 16 input channels and the change in package pinout require verification that your application does not depend on the additional 4 channels and that board-level modifications are feasible.

Q: What are the key differences between these two devices?

A: The primary differences are: (1) Number of inputs: TLC545IFN has 20 inputs; ADS7961SRHBT has 16 inputs. (2) Sampling rate: TLC545IFN operates at 76 kHz; ADS7961SRHBT operates at 1 MHz. (3) Package: TLC545IFN uses 28-PLCC; ADS7961SRHBT uses 32-VQFN. (4) Reference type: TLC545IFN supports both external and internal references; ADS7961SRHBT supports external reference only. (5) Product status: TLC545IFN is obsolete; ADS7961SRHBT is active.

Q: Is the ADS7961SRHBT compatible with 5V supply systems?

A: Yes. The ADS7961SRHBT operates across 2.7V ~ 5.25V for analog supply and 1.7V ~ 5.25V for digital supply, fully encompassing the 5V requirement of the original TLC545IFN design.

Q: What packaging considerations should I evaluate?

A: The TLC545IFN uses a 28-PLCC package while the ADS7961SRHBT uses a 32-VQFN package. These are different form factors requiring PCB layout modifications, including different pad patterns, trace routing, and potentially different board space allocation. Verify that your board design can accommodate the 32-VQFN footprint.

Q: Does the reduction from 20 to 16 input channels affect substitution feasibility?

A: This depends on your application. If your design uses all 20 channels, the ADS7961SRHBT cannot serve as a direct one-to-one replacement. If your design uses 16 or fewer channels, the ADS7961SRHBT is suitable. Evaluate your channel requirements before proceeding with substitution.

Q: Are both parts compliant with current regulatory standards?

A: Yes. Both the TLC545IFN and ADS7961SRHBT are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic components.