ZMM5239B-7 Equivalent & Substitute Parts

Part Overview

The ZMM5239B-7 is a Zener diode rated at 9.1 V nominal with 500 mW power dissipation in a Mini MELF surface mount package. Manufactured by Diodes Incorporated, this component is classified as obsolete. Due to its obsolete status and limited availability relative to active alternatives, equivalent substitute parts are necessary for ongoing design support and production continuity. Substitute parts maintain the core electrical specifications while offering improved availability and, in many cases, active product status from multiple manufacturers.

Key Parameters

Parameter	Value	Unit
Voltage - Zener (Nom)	9.1	V
Tolerance	±5%	-
Power - Max	500	mW
Impedance (Max)	10	Ohms
Current - Reverse Leakage @ Vr	3	µA @ 7 V
Voltage - Forward (Vf) (Max) @ If	1.5	V @ 200 mA
Operating Temperature	-65 to 175	°C
Mounting Type	Surface Mount	-
Package / Case	DO-213AC, MINI-MELF, SOD-80	-
RoHS Status	ROHS3 Compliant	-
Moisture Sensitivity Level	1 (Unlimited)	-

Substitute Part Grouping Explanation

Substitution of the ZMM5239B-7 is determined by the following critical parameters:

Primary Electrical Criteria:

Voltage - Zener (Nom): 9.1 V
Power - Max: 500 mW
Tolerance: ±5% (preferred for direct substitution)
Impedance (Max): 10 Ohms (or lower)
Current - Reverse Leakage @ Vr: 3 µA @ 7 V (or lower)
Operating Temperature Range: -65°C to 175°C (minimum requirement)

Secondary Criteria:

Mounting Type: Surface Mount
Package compatibility: DO-213AC/MINI-MELF/SOD-80 or equivalent surface mount packages
RoHS Compliance: ROHS3 preferred for regulatory alignment

Substitute parts are grouped into two categories:

Category A - Direct Electrical Equivalents (Same Vz, Power, Tolerance): Parts maintaining 9.1 V nominal voltage, 500 mW power rating, and ±5% tolerance with compatible surface mount packages. These include MMSZ5239B-7-F, 1N5239BUR-1, CDLL5239B, TLZ9V1-GS08, TLZ9V1-GS18, TLZ9V1A-GS08, and TLZ9V1A-GS18.

Category B - Functional Equivalents (Same Vz and Power, Relaxed Tolerance): Parts with 9.1 V nominal voltage and 500 mW power rating but with tolerance specifications of ±10% or ±20%. These include CDLL5239 and CDLL5239A. These parts are suitable for applications where tighter tolerance is not required.

Category C - Voltage Variant (Different Vz): The BZV55C11 operates at 11 V nominal voltage and is not a direct substitute but represents an alternative for circuits requiring higher zener voltage.

Parameter Comparison

Part Number	Manufacturer	Vz (Nom)	Tolerance	Power (Max)	Impedance (Max)	Reverse Leakage @ Vr	Vf (Max) @ If	Temp Range	Package	Product Status	RoHS
ZMM5239B-7	Diodes Inc.	9.1 V	±5%	500 mW	10 Ω	3 µA @ 7 V	1.5 V @ 200 mA	-65 to 175°C	Mini MELF	Obsolete	ROHS3
MMSZ5239B-7-F	Diodes Inc.	9.1 V	±5%	500 mW	10 Ω	3 µA @ 7 V	900 mV @ 10 mA	-65 to 150°C	SOD-123	Active	ROHS3
1N5239BUR-1	Microchip	9.1 V	±5%	500 mW	10 Ω	3 µA @ 7 V	1.1 V @ 200 mA	-65 to 175°C	DO-213AA	Active	Non-compliant
CDLL5239B	Microchip	9.1 V	±5%	-	10 Ω	3 µA @ 7 V	1.1 V @ 200 mA	-65 to 175°C	DO-213AB	Active	Non-compliant
CDLL5239A	Microchip	9.1 V	±10%	-	10 Ω	3 µA @ 7 V	1.1 V @ 200 mA	-65 to 175°C	DO-213AB	Active	Non-compliant
CDLL5239	Microchip	9.1 V	±20%	-	10 Ω	3 µA @ 7 V	1.1 V @ 200 mA	-65 to 175°C	DO-213AB	Active	Non-compliant
TLZ9V1-GS08	Vishay	9.1 V	-	500 mW	8.5 Ω	-	1.5 V @ 200 mA	-65 to 175°C	SOD-80	Active	ROHS3
TLZ9V1-GS18	Vishay	9.1 V	-	500 mW	8.5 Ω	-	1.5 V @ 200 mA	-65 to 175°C	SOD-80	Active	ROHS3
TLZ9V1A-GS08	Vishay	9.1 V	-	500 mW	8 Ω	40 nA @ 7.88 V	1.5 V @ 200 mA	-65 to 175°C	SOD-80	Active	ROHS3
TLZ9V1A-GS18	Vishay	9.1 V	-	500 mW	8 Ω	40 nA @ 7.88 V	1.5 V @ 200 mA	-65 to 175°C	SOD-80	Active	ROHS3
BZV55C11	Taiwan Semiconductor	11 V	±5%	500 mW	20 Ω	100 nA @ 8.2 V	1 V @ 10 mA	-65 to 175°C	Mini MELF	Active	ROHS3

Engineering Selection Recommendations

For Direct Replacement (Same Electrical and Thermal Performance):

MMSZ5239B-7-F from Diodes Incorporated is the primary recommended substitute. It maintains identical electrical specifications (9.1 V, ±5%, 500 mW) and RoHS3 compliance. The part is active with high inventory availability (47,200 units). The only difference is the package format (SOD-123 versus Mini MELF) and a slightly reduced maximum operating temperature (150°C versus 175°C). This substitute is suitable for applications where the SOD-123 package footprint is compatible with the circuit design.

TLZ9V1-GS08, TLZ9V1-GS18, TLZ9V1A-GS08, and TLZ9V1A-GS18 from Vishay are active alternatives maintaining 9.1 V nominal voltage, 500 mW power rating, and full -65°C to 175°C operating temperature range. These parts feature lower impedance (8 to 8.5 Ohms) and RoHS3 compliance. The TLZ9V1A variants offer superior reverse leakage characteristics (40 nA versus unspecified). All are packaged in SOD-80 (Mini MELF) format, matching the original package type.

For Applications Requiring Extended Temperature Range:

1N5239BUR-1 from Microchip Technology maintains the full -65°C to 175°C operating range with identical electrical specifications (9.1 V, ±5%, 500 mW). The part is active but carries RoHS non-compliant status. It is packaged in DO-213AA format.

CDLL5239B from Microchip Technology provides 9.1 V, ±5% tolerance with -65°C to 175°C operating range in DO-213AB package. RoHS non-compliant status applies.

For Applications with Relaxed Tolerance Requirements:

CDLL5239A (±10% tolerance) and CDLL5239 (±20% tolerance) from Microchip Technology are active alternatives suitable for circuits where tighter voltage tolerance is not critical. Both maintain 9.1 V nominal voltage and -65°C to 175°C operating range.

For RoHS3 Compliance Priority:

MMSZ5239B-7-F, TLZ9V1-GS08, TLZ9V1-GS18, TLZ9V1A-GS08, and TLZ9V1A-GS18 all carry ROHS3 Compliant status. These parts are preferred for applications subject to RoHS3 regulatory requirements.

Not Recommended for Direct Substitution:

BZV55C11 operates at 11 V nominal voltage and is not a direct electrical equivalent. This part is suitable only for circuit designs specifically requiring 11 V zener voltage.

Frequently Asked Questions (FAQ)

Q: Can MMSZ5239B-7-F replace ZMM5239B-7 directly?

A: MMSZ5239B-7-F maintains identical electrical specifications (9.1 V, ±5%, 500 mW, 10 Ω impedance, 3 µA reverse leakage). The primary difference is the package format: SOD-123 versus Mini MELF. Direct substitution is possible if the circuit board layout accommodates the SOD-123 footprint. The maximum operating temperature is 150°C compared to 175°C for the original part; verify this meets application requirements.

Q: What is the difference between the Vishay TLZ9V1 and TLZ9V1A variants?

A: Both maintain 9.1 V nominal voltage and 500 mW power rating. The TLZ9V1A variant features lower impedance (8 Ω versus 8.5 Ω) and specified reverse leakage current (40 nA @ 7.88 V). The TLZ9V1 variant does not specify reverse leakage. Both are packaged in SOD-80 (Mini MELF) format and operate across -65°C to 175°C.

Q: Are the Microchip CDLL5239 variants suitable substitutes?

A: CDLL5239B with ±5% tolerance is electrically equivalent to the original part. CDLL5239A (±10%) and CDLL5239 (±20%) offer relaxed tolerance specifications and are suitable for applications where voltage tolerance is not critical. All three maintain 9.1 V nominal voltage and -65°C to 175°C operating range. All are packaged in DO-213AB (MELF) format. RoHS non-compliant status applies to all Microchip variants.

Q: Why is BZV55C11 listed as a substitute if it has 11 V instead of 9.1 V?

A: BZV55C11 is not a direct substitute for the ZMM5239B-7. It is included in the reference for applications where a higher zener voltage (11 V) is required. It maintains the same 500 mW power rating and Mini MELF package format but operates at a different voltage level.

Q: What is the impact of package format differences on substitution?

A: The original ZMM5239B-7 uses Mini MELF (DO-213AC/SOD-80) package. Substitutes are available in SOD-123 (MMSZ5239B-7-F), DO-213AA (1N5239BUR-1), and DO-213AB (CDLL variants). Each package has different footprint dimensions and land patterns. Substitution requires verification that the circuit board layout and assembly equipment support the alternative package format.

Q: Which substitute offers the best availability?

A: MMSZ5239B-7-F from Diodes Incorporated has the highest inventory (47,200 units). Vishay TLZ9V1A-GS08 has 2,150 units in stock. All other substitutes have inventory below 1,000 units.

Q: Are all substitutes RoHS3 compliant?

A: No. MMSZ5239B-7-F and all Vishay TLZ variants (TLZ9V1-GS08, TLZ9V1-GS18, TLZ9V1A-GS08, TLZ9V1A-GS18) carry ROHS3 Compliant status. Microchip parts (1N5239BUR-1, CDLL5239, CDLL5239A, CDLL5239B) and Taiwan Semiconductor BZV55C11 have different compliance statuses. Verify RoHS requirements for your application before selection.

Q: What is the significance of impedance differences among substitutes?

A: The original ZMM5239B-7 specifies 10 Ω maximum impedance. Vishay TLZ variants offer lower impedance (8 to 8.5 Ω), which provides improved voltage regulation characteristics. BZV55C11 specifies 20 Ω impedance, which is higher. Lower impedance generally results in better load regulation and reduced output impedance in voltage regulation circuits.

Q: Can I use a substitute with a different tolerance rating?

A: Tolerance selection depends on circuit requirements. The original part specifies ±5%. CDLL5239B maintains ±5% tolerance. CDLL5239A offers ±10%, and CDLL5239 offers ±20%. Use tighter tolerance parts (±5%) for precision voltage reference applications. Relaxed tolerance parts are acceptable for general voltage regulation where voltage variation within ±10% or ±20% is tolerable.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message