PI74FCT543ATQ Equivalent & Substitute Parts

Part Overview

The PI74FCT543ATQ is a non-inverting transceiver logic IC manufactured by Diodes Incorporated, designed for 8-bit data transmission with 3-state output capability. Operating within the 4.75V to 5.25V supply range, this component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The 24-QSOP surface mount package provides compact integration for legacy and maintenance applications.

Substiute Parts

PI74FCT543ATQ

Diodes IncorporatedIn Stock: 1042PI74FCT543ATQ Datasheet

Current PartRFQ

CY74FCT2543ATQCT

Texas InstrumentsIn Stock: 4048CY74FCT2543ATQCT Datasheet

MFR RecommendedRFQ

CY74FCT2543CTQCT

Texas InstrumentsIn Stock: 3345CY74FCT2543CTQCT Datasheet

MFR RecommendedRFQ

CY74FCT543ATQCT

Texas InstrumentsIn Stock: 2944CY74FCT543ATQCT Datasheet

MFR RecommendedRFQ

CY74FCT543TQCT

Texas InstrumentsIn Stock: 1055CY74FCT543TQCT Datasheet

MFR RecommendedRFQ

74FCT543ATQG

Renesas Electronics CorporationIn Stock: 132974FCT543ATQG Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the PI74FCT543ATQ is determined by the following critical parameters:

• Logic type and function: Transceiver, Non-Inverting with 1 element and 8 bits per element
• Output configuration: 3-State output capability
• Electrical specifications: Supply voltage 4.75V ~ 5.25V and operating temperature -40°C ~ 85°C
• Package compatibility: 24-SSOP (0.154", 3.90mm Width) physical dimensions
• Output current ratings: High and low output current specifications

Substitute parts are grouped into two categories:

MFR Recommended Substitutes maintain full functional and electrical equivalence with active product status and modern RoHS3 compliance.

Parametric Equivalent provides functional compatibility with matching electrical characteristics but may have different product lifecycle status or compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

For Active Production Requirements:

CY74FCT543ATQCT and CY74FCT543TQCT from Texas Instruments are the primary recommended substitutes. Both maintain active product status with ROHS3 compliance, ensuring long-term availability and regulatory alignment. CY74FCT543ATQCT matches the original output current specifications (32mA / 64mA) and is available in Tape & Reel packaging. CY74FCT543TQCT provides identical electrical performance with alternative Cut Tape packaging.

For RoHS3 Compliance Requirement:

All Texas Instruments and Renesas Electronics substitutes (CY74FCT2543ATQCT, CY74FCT2543CTQCT, CY74FCT543ATQCT, CY74FCT543TQCT, and 74FCT543ATQG) meet ROHS3 compliance standards, addressing regulatory requirements that the original PI74FCT543ATQ does not satisfy.

For Output Current Matching:

CY74FCT543ATQCT, CY74FCT543TQCT, and 74FCT543ATQG maintain the original 15mA / 64mA or 32mA / 64mA output current specifications. CY74FCT2543ATQCT and CY74FCT2543CTQCT provide reduced low-side output current (12mA) and are suitable only where lower output current is acceptable.

For Moisture Sensitivity Considerations:

74FCT543ATQG from Renesas Electronics maintains MSL 1 (Unlimited) rating, matching the original component. Texas Instruments substitutes carry MSL 2 (1 Year) rating, requiring controlled storage and handling procedures.

Frequently Asked Questions (FAQ)

Q: Can CY74FCT2543ATQCT replace PI74FCT543ATQ directly?

A: CY74FCT2543ATQCT is functionally equivalent in logic type, bit configuration, and supply voltage. However, the output low current is reduced from 64mA to 12mA. This substitute is suitable only if the circuit design accommodates the lower output current specification.

Q: What is the difference between CY74FCT543ATQCT and CY74FCT543TQCT?

A: Both parts are electrically identical with matching output current specifications (32mA / 64mA). The primary difference is packaging: CY74FCT543ATQCT is supplied in Tape & Reel (TR) format, while CY74FCT543TQCT is supplied in Cut Tape (CT) & Digi-Reel® format. Selection depends on assembly equipment compatibility and volume requirements.

Q: Is 74FCT543ATQG from Renesas Electronics a suitable replacement?

A: 74FCT543ATQG provides parametric equivalence with matching output current (15mA / 64mA) and MSL 1 rating. However, the product status is Last Time Buy, indicating limited future availability. This part is suitable for legacy system maintenance but not recommended for new production designs.

Q: Why do some substitutes have different output current ratings?

A: Output current specifications vary between manufacturers and product lines. CY74FCT2543 series provides 15mA / 12mA, while CY74FCT543 series provides 32mA / 64mA. Circuit design must verify that the selected substitute's output current meets the application's load requirements.

Q: What does ROHS3 compliance mean for this component?

A: ROHS3 compliance indicates the part meets Restriction of Hazardous Substances Directive requirements, restricting lead, cadmium, mercury, and other hazardous materials. The original PI74FCT543ATQ is RoHS non-compliant. All recommended substitutes are ROHS3 compliant, supporting modern regulatory and procurement standards.

Q: Are all substitutes compatible with the 24-SSOP package footprint?

A: All listed substitutes use the 24-SSOP (0.154", 3.90mm Width) package, providing mechanical and electrical pin compatibility. PCB footprints designed for PI74FCT543ATQ accommodate all substitute parts without modification.

Q: What is the significance of Moisture Sensitivity Level (MSL) differences?

A: MSL 1 (Unlimited) components like PI74FCT543ATQ and 74FCT543ATQG require no special moisture control. MSL 2 (1 Year) components like Texas Instruments substitutes require storage in controlled humidity environments and have a one-year shelf life after opening. Handling procedures must reflect the selected part's MSL rating.