74F521PC Equivalent & Substitute Parts

Part Overview

The 74F521PC is an 8-bit identity comparator manufactured by onsemi, designed to perform magnitude comparison operations with active low output logic. This device compares two 8-bit inputs and provides an A=B output function. The 74F521PC is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The Texas Instruments SN74F521N provides a direct functional and electrical equivalent with active product status.

Substiute Parts

74F521PC

onsemiIn Stock: 955274F521PC Datasheet

Current PartRFQ

SN74F521N

Texas InstrumentsIn Stock: 2128SN74F521N Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The SN74F521N qualifies as a direct substitute for the 74F521PC based on the following critical parameters:

• Functional Equivalence: Both devices are 8-bit identity comparators with identical A=B output function and active low output logic
• Electrical Specifications: Matching supply voltage range (4.5V ~ 5.5V), output current ratings (1mA/20mA), and propagation delay (10ns @ 5V, 50pF)
• Operating Conditions: Identical operating temperature range (0°C ~ 70°C)
• Package Compatibility: Both use 20-DIP (0.300", 7.62mm) through-hole packaging with identical pin configurations
• Series Compatibility: Both belong to the 74F logic series

Parameter Comparison

Engineering Selection Recommendations

The SN74F521N is the recommended substitute for the 74F521PC. The primary advantage is product status: the SN74F521N maintains active manufacturing status with 2100 units in stock, whereas the 74F521PC is obsolete. Both devices meet identical electrical and mechanical specifications, ensuring direct functional compatibility in existing circuit designs. The SN74F521N carries RoHS3 compliance, providing additional regulatory alignment for new production. Both parts maintain REACH Unaffected status and EAR99 export classification, ensuring consistent compliance requirements.

Frequently Asked Questions (FAQ)

Q: Can the SN74F521N directly replace the 74F521PC in existing designs? A: Yes. The SN74F521N provides complete electrical and mechanical equivalence. All critical parameters—supply voltage, output logic, propagation delay, and package configuration—are identical. Direct socket substitution is possible without circuit modification.

Q: Are there any differences in output characteristics between these devices? A: No. Both devices specify identical output current ratings (1mA high, 20mA low) and propagation delay (10ns @ 5V, 50pF). Output behavior under identical load conditions will be equivalent.

Q: What is the significance of the product status difference? A: The 74F521PC is obsolete, meaning onsemi no longer manufactures this device. The SN74F521N is actively produced by Texas Instruments, ensuring long-term availability and supply chain continuity for new designs and production runs.

Q: Are the packaging and pinout identical? A: Yes. Both devices use 20-DIP (0.300", 7.62mm) through-hole packaging with identical pin assignments. PCB layouts and mechanical mounting requirements are interchangeable.

Q: Do compliance certifications differ between the two parts? A: Both maintain REACH Unaffected status and EAR99 export classification. The SN74F521N additionally carries RoHS3 compliance, which may be required for certain applications or markets.