TZMB33-GS18 Equivalent & Substitute Parts

Part Overview

The TZMB33-GS18 is a Zener diode rated at 33 V nominal voltage with 500 mW power dissipation, manufactured by Vishay General Semiconductor - Diodes Division. This surface mount component is packaged in SOD-80 MiniMELF format and is qualified to AEC-Q101 automotive standards. The part is currently active in production with 763 pieces in stock. Equivalent and substitute parts are identified when component availability is limited, supply chain disruptions occur, or design flexibility is required while maintaining electrical and mechanical compatibility within specified tolerances.

Substiute Parts

TZMB33-GS18

Vishay General Semiconductor - Diodes DivisionIn Stock: 823TZMB33-GS18 Datasheet

Current PartRFQ

TZMB33-GS08

Vishay General Semiconductor - Diodes DivisionIn Stock: 45286TZMB33-GS08 Datasheet

Parametric EquivalentRFQ

CLL5257B TR PBFREE

Central Semiconductor CorpIn Stock: 12528CLL5257B TR PBFREE Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the TZMB33-GS18 are classified based on strict electrical and mechanical parameter alignment. The primary substitution criteria are:

Critical Parameters (Must Match):

• Zener voltage: 33 V nominal
• Power rating: 500 mW maximum
• Package type: SOD-80 MiniMELF (DO-213AC)
• Mounting type: Surface Mount

Allowable Variations:

• Tolerance: ±2% to ±5% (wider tolerance acceptable for functional equivalence)
• Impedance (Zzt): 58 to 80 Ohms (within acceptable operating range)
• Reverse leakage current: 100 nA specification maintained
• Forward voltage: 1.25 to 1.5 V (minor variation acceptable)
• Operating temperature: -65°C minimum to 175°C or higher maximum
• Compliance and qualification status: Active product status with RoHS3 compliance

Substitutes are grouped into two categories: Parametric Equivalent (identical electrical specifications with different packaging format) and Manufacturer Recommended (functionally equivalent with minor specification variations).

Parameter Comparison

Engineering Selection Recommendations

TZMB33-GS08 (Parametric Equivalent)

The TZMB33-GS08 is a direct parametric equivalent to the TZMB33-GS18. Both parts are manufactured by Vishay General Semiconductor within the TZM series and share identical electrical specifications: 33 V nominal zener voltage, ±2% tolerance, 500 mW power rating, 80 Ohms maximum impedance, and -65°C to 175°C operating temperature range. Both parts carry AEC-Q101 automotive qualification and ROHS3 compliance. The primary difference is packaging format: TZMB33-GS18 is supplied in Tape & Reel (TR) format, while TZMB33-GS08 is available in Cut Tape (CT) and Digi-Reel® format. This substitute is suitable for applications requiring identical electrical performance with alternative tape packaging. Significantly higher inventory availability (45200 pieces) supports supply chain flexibility.

CLL5257B TR PBFREE (Manufacturer Recommended)

The CLL5257B TR PBFREE, manufactured by Central Semiconductor Corp, is a functionally equivalent alternative with allowable specification variations. This part maintains the 33 V nominal zener voltage, 500 mW power rating, and SOD-80 MiniMELF package format. Specification differences include: tolerance of ±5% (versus ±2%), impedance of 58 Ohms (versus 80 Ohms), forward voltage of 1.25 V (versus 1.5 V), and extended operating temperature range to 200°C (versus 175°C). The CLL5257B TR PBFREE does not carry automotive grade or AEC-Q101 qualification. This substitute is applicable for non-automotive applications or where the wider tolerance and lower impedance are acceptable. Adequate inventory (12492 pieces) is available.

Frequently Asked Questions (FAQ)

Q: Can TZMB33-GS08 be used as a direct replacement for TZMB33-GS18?

A: Yes. The TZMB33-GS08 is a parametric equivalent with identical electrical specifications and automotive qualification. The only difference is the packaging format (Cut Tape/Digi-Reel versus Tape & Reel). Both parts are suitable for the same circuit applications.

Q: What are the key differences between TZMB33-GS18 and CLL5257B TR PBFREE?

A: The CLL5257B TR PBFREE has a wider tolerance specification (±5% versus ±2%), lower impedance (58 Ohms versus 80 Ohms), lower forward voltage (1.25 V versus 1.5 V), and an extended upper operating temperature limit (200°C versus 175°C). The CLL5257B lacks automotive grade and AEC-Q101 qualification. These differences may affect circuit performance in precision applications or automotive environments.

Q: Is the CLL5257B TR PBFREE suitable for automotive applications?

A: The CLL5257B TR PBFREE does not carry automotive grade designation or AEC-Q101 qualification. For automotive applications requiring AEC-Q101 compliance, use TZMB33-GS18 or TZMB33-GS08.

Q: What does the ±2% tolerance mean for the TZMB33-GS18?

A: The ±2% tolerance indicates that the actual zener voltage will be within 2% of the 33 V nominal specification, resulting in a range of 32.34 V to 33.66 V. The CLL5257B TR PBFREE has ±5% tolerance, resulting in a range of 31.35 V to 34.65 V.

Q: Are all three parts RoHS3 compliant?

A: Yes. TZMB33-GS18, TZMB33-GS08, and CLL5257B TR PBFREE are all ROHS3 compliant with Moisture Sensitivity Level 1 (Unlimited).

Q: What is the significance of the SOD-80 MiniMELF package?

A: SOD-80 MiniMELF is a surface mount package format for small signal diodes. All three substitute parts use this identical package, ensuring mechanical and thermal compatibility in PCB designs. The package supports automated assembly processes.

Q: Can impedance differences affect circuit performance?

A: Yes. Impedance affects the dynamic resistance of the zener diode. The TZMB33-GS18 and TZMB33-GS08 have 80 Ohms maximum impedance, while CLL5257B TR PBFREE has 58 Ohms. Lower impedance results in better voltage regulation under load changes. For precision voltage regulation circuits, impedance matching is important.

Q: What is the difference between Tape & Reel (TR) and Cut Tape (CT) packaging?

A: Tape & Reel (TR) packaging supplies components on continuous reels suitable for high-volume automated assembly. Cut Tape (CT) supplies components on tape segments for lower-volume or manual assembly. Both formats contain the same component; the difference is in supply format and handling.