LZ52C33W Equivalent & Substitute Parts

Part Overview

The LZ52C33W is a Zener diode manufactured by Diodes Incorporated, rated at 33 V nominal voltage with 500 mW maximum power dissipation. This component is designed for surface mount applications in the 1206 (3216 Metric) package. The part is classified as obsolete, necessitating identification of active equivalent alternatives that maintain functional compatibility while ensuring continued supply chain availability and design continuity.

Substiute Parts

LZ52C33W

Diodes IncorporatedIn Stock: 1015LZ52C33W Datasheet

Current PartRFQ

BZT52C33-7-F

Diodes IncorporatedIn Stock: 21215BZT52C33-7-F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LZ52C33W is determined by the following critical electrical and mechanical parameters:

Electrical Compatibility Criteria:

• Nominal Zener voltage of 33 V
• Maximum power dissipation of 500 mW
• Impedance (Max) of 80 Ohms
• Reverse leakage current specification of 100 nA
• Operating temperature range capability

Mechanical Compatibility Criteria:

• Surface mount mounting type
• Package compatibility (SOD-123 is functionally equivalent to 1206 for this diode category)

Compliance Requirements:

• ROHS3 compliance
• Moisture Sensitivity Level 1 (Unlimited)
• REACH Unaffected status

The substitute part BZT52C33-7-F meets all critical electrical parameters and compliance requirements. While the tolerance specification differs (±6% versus ±2%) and the package designation differs (SOD-123 versus 1206), both packages are standard surface mount configurations for Zener diodes in this power class and voltage rating. The operating temperature range of the substitute extends to 150°C (versus 175°C for the main part), which remains within acceptable limits for most applications.

Parameter Comparison

Engineering Selection Recommendations

The BZT52C33-7-F is the manufacturer-recommended substitute for the obsolete LZ52C33W. Both components are manufactured by Diodes Incorporated and share identical nominal voltage, power rating, and impedance specifications. The substitute part is currently in active production status with substantial inventory availability (21,200 pieces), ensuring supply chain continuity.

Key considerations for selection:

Tolerance Specification: The substitute part carries a ±6% tolerance compared to the main part's ±2% tolerance. Applications requiring tighter voltage regulation should evaluate whether this tolerance variance affects circuit performance.

Package Configuration: The SOD-123 package of the substitute differs in designation from the 1206 package of the main part. Both are standard surface mount packages for Zener diodes in this power class. PCB layout and footprint compatibility must be verified during design transition.

Operating Temperature: The substitute part operates to 150°C maximum junction temperature, compared to 175°C for the main part. Applications operating near the upper temperature limit require thermal analysis to confirm the reduced range is acceptable.

Compliance Status: Both parts maintain ROHS3 compliance, REACH Unaffected status, and Moisture Sensitivity Level 1 (Unlimited), ensuring regulatory and environmental compatibility.

Frequently Asked Questions (FAQ)

Q: Can BZT52C33-7-F directly replace LZ52C33W in existing designs?

A: Electrical substitution is valid based on matching nominal voltage (33 V), power rating (500 mW), and impedance (80 Ohms). Physical substitution requires PCB footprint verification, as the package designations differ (SOD-123 versus 1206). Tolerance and temperature range differences must be evaluated against specific application requirements.

Q: What is the significance of the tolerance difference between ±2% and ±6%?

A: The main part specifies ±2% tolerance, while the substitute specifies ±6% tolerance. This means the substitute's actual Zener voltage may deviate up to ±6% from the nominal 33 V value. Applications with strict voltage regulation requirements should confirm this tolerance variance does not exceed circuit specifications.

Q: Are SOD-123 and 1206 packages interchangeable?

A: SOD-123 and 1206 are different package designations for surface mount diodes. While both are standard surface mount configurations, they have different physical dimensions and footprints. PCB layout compatibility must be verified before substitution. Consult package datasheets for exact dimensions and land pattern requirements.

Q: Does the reduced operating temperature range (150°C vs. 175°C) affect suitability?

A: The substitute part's maximum junction temperature of 150°C is lower than the main part's 175°C. For applications operating near or above 150°C, thermal analysis is required to confirm the substitute remains within acceptable operating conditions. Most standard applications operate well below this threshold.

Q: Are both parts RoHS and REACH compliant?

A: Yes, both the LZ52C33W and BZT52C33-7-F are ROHS3 compliant and REACH Unaffected. Both maintain Moisture Sensitivity Level 1 (Unlimited), indicating no special moisture handling requirements during storage or assembly.

Q: Why is the main part obsolete while the substitute is active?

A: The LZ52C33W is classified as obsolete, indicating it is no longer in production. The BZT52C33-7-F is the active equivalent from the same manufacturer, offering the same core electrical specifications with current production status and supply availability. Transition to the active part ensures long-term component availability.