FLZ27VB Equivalent & Substitute Parts

Part Overview

The FLZ27VB is a Zener diode manufactured by onsemi, rated at 25.6 V nominal with 500 mW power dissipation capability in a surface mount SOD-80 package. This component is classified as obsolete, necessitating identification of functionally equivalent alternatives for ongoing design support and procurement continuity. Substitute parts must maintain electrical performance within acceptable circuit tolerances while meeting current availability and compliance requirements.

Substiute Parts

FLZ27VB

onsemiIn Stock: 7855FLZ27VB Datasheet

Current PartRFQ

BZV55-C24,135

NXP SemiconductorsIn Stock: 220948BZV55-C24,135 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FLZ27VB is based on the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Zener voltage nominal rating within circuit tolerance requirements
• Power dissipation capacity of 500 mW minimum
• Surface mount package compatibility (SOD-80 / DO-213AC / MINI-MELF)
• Operating temperature range encompassing -65°C to 175°C minimum

Mechanical Compatibility Criteria:

• Identical or equivalent package footprint (SOD-80 / MINI-MELF)
• Surface mount mounting type

The BZV55-C24,135 from NXP Semiconductors meets these substitution criteria with a nominal Zener voltage of 24 V (1.6 V deviation from the FLZ27VB), matching power rating, package type, and surface mount configuration. The substitute part is classified as active product status, ensuring ongoing availability and supply chain continuity.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: BZV55-C24,135 (NXP Semiconductors)

The BZV55-C24,135 is the qualified substitute for the obsolete FLZ27VB. Selection is based on the following engineering factors:

Compliance & Availability:

• Active product status ensures long-term supply chain continuity
• REACH Unaffected classification matches the original part
• Moisture Sensitivity Level 1 (Unlimited) provides equivalent handling requirements

Electrical Performance:

• Nominal Zener voltage of 24 V operates within acceptable circuit tolerance for most 25.6 V applications, representing a -6.25% deviation
• Matched 500 mW power dissipation capacity
• Extended operating temperature range (-65 to 200°C) provides superior thermal performance

Mechanical Compatibility:

• Identical surface mount package (SOD-80 / MINI-MELF / DO-213AC)
• Direct footprint compatibility with existing PCB designs

Design Considerations:

• The 1.6 V lower nominal voltage requires circuit-level verification for voltage regulation and protection applications
• Higher impedance (70 Ohms vs. 38 Ohms) may affect transient response characteristics
• Wider tolerance specification (±5% vs. ±3%) should be evaluated against circuit margin requirements

Frequently Asked Questions (FAQ)

Q: Can the BZV55-C24,135 be used as a direct replacement for the FLZ27VB?

A: The BZV55-C24,135 is mechanically and functionally compatible as a substitute. Both components share identical surface mount packaging (SOD-80 / MINI-MELF), power rating (500 mW), and operating temperature range. However, the 1.6 V lower nominal Zener voltage must be evaluated within the specific circuit application to confirm acceptable performance margins.

Q: What is the voltage difference between these parts, and does it matter?

A: The FLZ27VB is rated at 25.6 V nominal, while the BZV55-C24,135 is rated at 24 V nominal, representing a -6.25% deviation. For voltage regulation and overvoltage protection circuits, this difference may be significant. Circuit designers must verify that the lower voltage threshold does not compromise protection or regulation performance in the target application.

Q: Are the package dimensions identical?

A: Both the FLZ27VB and BZV55-C24,135 use the SOD-80 / MINI-MELF / DO-213AC package designation. This package type is standardized, ensuring mechanical and footprint compatibility. No PCB layout modifications are required for physical substitution.

Q: What is the impedance difference, and how does it affect circuit performance?

A: The FLZ27VB has a maximum impedance of 38 Ohms, while the BZV55-C24,135 has a maximum impedance of 70 Ohms. Higher impedance affects the transient response and voltage regulation characteristics of the Zener diode. In applications requiring fast transient suppression or tight voltage regulation, this difference should be evaluated through circuit simulation or testing.

Q: Why is the FLZ27VB obsolete, and is the substitute actively manufactured?

A: The FLZ27VB is classified as obsolete by onsemi, indicating discontinued production. The BZV55-C24,135 is classified as active product status by NXP Semiconductors, confirming ongoing manufacture and availability. This substitution ensures procurement continuity and long-term supply chain reliability.

Q: Are there any compliance or certification differences?

A: Both parts are REACH Unaffected and carry Moisture Sensitivity Level 1 (Unlimited), indicating equivalent environmental and handling compliance. No additional certification or compliance modifications are required for substitution.

Q: What tolerance specifications should I consider?

A: The FLZ27VB carries a ±3% tolerance specification, while the BZV55-C24,135 carries a ±5% tolerance. The wider tolerance of the substitute part may affect circuit performance in applications with tight voltage regulation requirements. Circuit margin analysis is recommended for precision voltage reference or protection applications.