MMBZ5259C-E3-08 Equivalent & Substitute Parts

Part Overview

The MMBZ5259C-E3-08 is a 39 V Zener diode rated at 225 mW in a surface mount SOT-23-3 package, manufactured by Vishay General Semiconductor - Diodes Division. This component is classified as obsolete, necessitating identification of active equivalent parts for ongoing design requirements and production continuity. Substitute parts must maintain electrical compatibility across voltage regulation, power dissipation, and thermal operating ranges while accommodating the SOT-23-3 surface mount package standard.

Key Parameters

Parameter	Value	Unit
Voltage - Zener (Nominal)	39	V
Power - Maximum	225	mW
Tolerance	±2%	—
Impedance (Maximum)	80	Ohms
Current - Reverse Leakage @ Vr	100 nA @ 30 V	—
Operating Temperature Range	-55 to 150	°C
Mounting Type	Surface Mount	—
Package / Case	TO-236-3, SC-59, SOT-23-3	—
RoHS Status	ROHS3 Compliant	—

Substitute Part Grouping Explanation

Substitution of the MMBZ5259C-E3-08 is determined by the following critical parameters:

Primary Compatibility Criteria:

Zener voltage: 39 V nominal
Package type: SOT-23-3 surface mount
Mounting configuration: Surface mount
Regulatory compliance: RoHS3 compliant

Secondary Compatibility Criteria:

Power dissipation rating: Equal to or greater than 225 mW
Impedance: 80 Ohms or lower
Reverse leakage current: 100 nA @ 30 V or lower
Operating temperature range: Minimum -55°C to 150°C

All identified substitute parts maintain the 39 V Zener voltage specification and SOT-23-3 package format. Substitute parts with higher power ratings (350 mW) provide enhanced thermal margin. Tolerance variations (±5% versus ±2%) are acceptable within standard voltage regulation applications where the nominal 39 V specification is maintained.

Parameter Comparison

Parameter	MMBZ5259C-E3-08 (Main)	CMPZ5259B TR PBFREE	CZRT55C39-G	MMBZ5259BLT1G	SZMMBZ5259BLT1G
Manufacturer	Vishay General Semiconductor	Central Semiconductor Corp	Comchip Technology	onsemi	onsemi
Voltage - Zener (Nom)	39 V	39 V	39 V	39 V	39 V
Tolerance	±2%	±5%	±5%	±5%	±5%
Power - Max	225 mW	350 mW	350 mW	225 mW	225 mW
Impedance (Max)	80 Ohms	80 Ohms	130 Ohms	80 Ohms	80 Ohms
Current - Reverse Leakage @ Vr	100 nA @ 30 V	100 nA @ 30 V	100 nA @ 27.3 V	100 nA @ 30 V	100 nA @ 30 V
Operating Temperature	-55 to 150°C	-65 to 150°C	-65 to 150°C	-65 to 150°C	-65 to 150°C
Package / Case	TO-236-3, SC-59, SOT-23-3	TO-236-3, SC-59, SOT-23-3	TO-236-3, SC-59, SOT-23-3	TO-236-3, SC-59, SOT-23-3	TO-236-3, SC-59, SOT-23-3
Product Status	Obsolete	Active	Active	Active	Active
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant
Moisture Sensitivity Level	1 (Unlimited)	1 (Unlimited)	1 (Unlimited)	1 (Unlimited)	1 (Unlimited)
REACH Status	REACH Unaffected	REACH Unaffected	REACH Unaffected	REACH Unaffected	REACH Unaffected

Engineering Selection Recommendations

Primary Substitutes (Highest Compatibility):

MMBZ5259BLT1G and SZMMBZ5259BLT1G (onsemi) are direct functional equivalents with active product status. Both maintain the 225 mW power rating, 80 Ohm impedance, and identical reverse leakage characteristics. SZMMBZ5259BLT1G includes AEC-Q101 automotive qualification, suitable for applications requiring automotive-grade reliability. Both parts extend the operating temperature range to -65°C, providing enhanced low-temperature performance.

Secondary Substitutes (Enhanced Power Rating):

CMPZ5259B TR PBFREE (Central Semiconductor Corp) and CZRT55C39-G (Comchip Technology) provide 350 mW power dissipation, offering 55% greater thermal margin than the original specification. These parts are suitable for applications where increased power handling improves thermal stability. CMPZ5259B maintains 80 Ohm impedance matching the original part. CZRT55C39-G operates at 130 Ohm impedance, acceptable for voltage regulation applications where impedance variation does not compromise circuit performance.

All substitute parts maintain RoHS3 compliance, REACH unaffected status, and MSL 1 moisture sensitivity rating. Selection between substitutes depends on specific application requirements for power dissipation margin, temperature range, and automotive qualification status.

Frequently Asked Questions (FAQ)

Q: Can CMPZ5259B TR PBFREE or CZRT55C39-G be used as direct replacements for MMBZ5259C-E3-08?

A: Yes. Both parts maintain the 39 V Zener voltage specification and SOT-23-3 package format. The increased 350 mW power rating provides additional thermal margin. CZRT55C39-G operates at 130 Ohm impedance versus the original 80 Ohm specification; this difference is acceptable in standard voltage regulation circuits where impedance variation does not affect circuit performance.

Q: What is the difference between MMBZ5259BLT1G and SZMMBZ5259BLT1G?

A: Both parts are manufactured by onsemi with identical electrical specifications: 39 V Zener voltage, 225 mW power rating, and 80 Ohm impedance. SZMMBZ5259BLT1G includes AEC-Q101 automotive qualification and automotive-grade designation, required for automotive applications. MMBZ5259BLT1G is suitable for general industrial and commercial applications.

Q: Does the ±5% tolerance of substitute parts affect circuit performance compared to the ±2% tolerance of MMBZ5259C-E3-08?

A: Tolerance differences are application-dependent. The ±5% tolerance of substitute parts results in a Zener voltage range of 37.05 V to 40.95 V versus 38.22 V to 39.78 V for the original ±2% specification. Applications requiring tighter voltage regulation should evaluate circuit performance across the full tolerance range of substitute parts.

Q: Are all substitute parts available in the same packaging format?

A: Yes. All substitute parts are packaged in TO-236-3, SC-59, SOT-23-3 surface mount format, identical to the original MMBZ5259C-E3-08. Tape & Reel (TR) packaging is available for all substitutes, suitable for automated assembly processes.

Q: What is the operating temperature advantage of substitute parts?

A: The original MMBZ5259C-E3-08 operates from -55°C to 150°C. All substitute parts extend the minimum operating temperature to -65°C, providing 10°C additional low-temperature performance margin. Maximum operating temperature remains 150°C across all parts.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All identified substitute parts maintain ROHS3 compliance and REACH unaffected status, meeting current environmental and regulatory requirements for electronic component manufacturing and distribution.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message