VLZ33D-GS08 Equivalent & Substitute Parts

Part Overview

The VLZ33D-GS08 is a Zener diode rated at 32.3 V nominal voltage with 500 mW power dissipation, manufactured by Vishay General Semiconductor - Diodes Division. This component is packaged in SOD-80 QuadroMELF surface mount configuration and is qualified to AEC-Q101 automotive standards. The part is currently classified as obsolete, necessitating identification of equivalent and substitute components for ongoing design support and procurement continuity.

Key Parameters

Parameter	Value
Voltage - Zener (Nom)	32.3 V
Power - Max	500 mW
Impedance (Max)	65 Ohms
Current - Reverse Leakage @ Vr	40 µA @ 29.9 V
Voltage - Forward (Vf) (Max) @ If	1.5 V @ 200 mA
Operating Temperature Range	-65°C ~ 175°C
Mounting Type	Surface Mount
Package / Case	SOD-80 QuadroMELF
Grade	Automotive
Qualification	AEC-Q101
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution of the VLZ33D-GS08 is determined by the following critical parameters:

Voltage Compatibility: The nominal Zener voltage must fall within acceptable tolerance of the original 32.3 V specification. Substitute parts rated at 33 V nominal voltage are functionally equivalent within standard circuit design margins.

Power Dissipation: All substitute parts must maintain the 500 mW maximum power rating to ensure thermal performance equivalence.

Impedance Characteristics: Maximum impedance values determine dynamic response and regulation quality. The original part specifies 65 Ohms maximum impedance.

Reverse Leakage Current: Leakage specifications affect circuit performance in high-impedance applications and must be comparable to the original 40 µA @ 29.9 V.

Operating Temperature Range: All substitutes must support the full -65°C to 175°C operating window to maintain automotive-grade reliability.

Surface Mount Configuration: All substitute parts are surface mount devices, maintaining PCB assembly compatibility.

Compliance Standards: RoHS3 compliance and REACH unaffected status are maintained across all substitute options.

Parameter Comparison

Parameter	VLZ33D-GS08 (Main)	TLZ33D-GS08 (Substitute)	1N4121UR-1 (Substitute)
Manufacturer	Vishay General Semiconductor	Vishay General Semiconductor	Microchip Technology
Voltage - Zener (Nom)	32.3 V	33 V	33 V
Power - Max	500 mW	500 mW	500 mW
Impedance (Max)	65 Ohms	65 Ohms	200 Ohms
Current - Reverse Leakage @ Vr	40 µA @ 29.9 V	40 nA @ 29.9 V	10 nA @ 25.1 V
Voltage - Forward (Vf) (Max) @ If	1.5 V @ 200 mA	1.5 V @ 200 mA	1.1 V @ 200 mA
Operating Temperature Range	-65°C ~ 175°C	-65°C ~ 175°C	-65°C ~ 175°C
Mounting Type	Surface Mount	Surface Mount	Surface Mount
Package / Case	SOD-80 QuadroMELF	SOD-80 MiniMELF	DO-213AA
Product Status	Obsolete	Active	Active
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	RoHS non-compliant

Engineering Selection Recommendations

TLZ33D-GS08 (Vishay General Semiconductor)

The TLZ33D-GS08 is the primary substitute for the obsolete VLZ33D-GS08. Both components are manufactured by Vishay General Semiconductor and share identical electrical specifications: 33 V nominal Zener voltage, 500 mW power rating, and 65 Ohms maximum impedance. The TLZ33D-GS08 maintains full compliance with ROHS3 standards and operates across the identical -65°C to 175°C temperature range. The component is currently in active production with substantial inventory availability (42,600 units). The primary difference is the package variant: TLZ33D-GS08 uses SOD-80 MiniMELF (DO-213AC) versus the original QuadroMELF configuration. This package change requires PCB layout verification but does not affect electrical performance. The reverse leakage current of 40 nA at 29.9 V represents an improvement over the original specification.

1N4121UR-1 (Microchip Technology)

The 1N4121UR-1 is an alternative substitute manufactured by Microchip Technology. This component meets the core electrical requirements: 33 V nominal Zener voltage and 500 mW power rating. The operating temperature range matches the original specification at -65°C to 175°C. However, this part exhibits three significant deviations: (1) impedance of 200 Ohms maximum, which is 3.08 times higher than the original 65 Ohms specification; (2) RoHS non-compliance status, which may conflict with procurement requirements; (3) package configuration of DO-213AA, which differs from both the original and primary substitute. The lower forward voltage (1.1 V @ 200 mA) and superior reverse leakage characteristics (10 nA @ 25.1 V) represent performance improvements. Selection of this part requires confirmation that the higher impedance and RoHS non-compliance status are acceptable for the intended application.

Frequently Asked Questions (FAQ)

Q: Can the TLZ33D-GS08 be used as a direct replacement for the VLZ33D-GS08?

A: The TLZ33D-GS08 is electrically equivalent to the VLZ33D-GS08 with respect to Zener voltage (33 V vs. 32.3 V), power dissipation (500 mW), impedance (65 Ohms), and operating temperature range (-65°C to 175°C). The primary consideration is the package change from SOD-80 QuadroMELF to SOD-80 MiniMELF (DO-213AC). PCB footprint and land pattern verification is required before implementation.

Q: What is the significance of the impedance difference between the TLZ33D-GS08 and 1N4121UR-1?

A: Impedance (Zzt) affects the dynamic regulation characteristics of the Zener diode. The TLZ33D-GS08 maintains 65 Ohms maximum impedance, matching the original VLZ33D-GS08. The 1N4121UR-1 specifies 200 Ohms maximum impedance, which results in greater voltage variation across the diode under changing load conditions. Applications requiring tight voltage regulation should prioritize the TLZ33D-GS08.

Q: Why is the 1N4121UR-1 marked as RoHS non-compliant?

A: RoHS non-compliance indicates the component may contain restricted substances such as lead or other hazardous materials. Selection of this part requires confirmation that the application environment and regulatory requirements permit non-compliant components.

Q: Are there package compatibility issues between the substitute parts?

A: Yes. The VLZ33D-GS08 uses SOD-80 QuadroMELF packaging. The TLZ33D-GS08 uses SOD-80 MiniMELF (DO-213AC), and the 1N4121UR-1 uses DO-213AA. These packages have different physical dimensions and land patterns. PCB layout modification is required for either substitute. Consult component datasheets for precise footprint specifications.

Q: What is the voltage tolerance difference between the main part and substitutes?

A: The VLZ33D-GS08 does not specify a tolerance value in the provided data. The TLZ33D-GS08 also does not specify tolerance. The 1N4121UR-1 specifies ±5% tolerance. For applications requiring tight voltage tolerance, contact the manufacturer for tolerance specifications on the Vishay parts.

Q: Can the reverse leakage current differences affect circuit performance?

A: The VLZ33D-GS08 specifies 40 µA reverse leakage at 29.9 V. The TLZ33D-GS08 specifies 40 nA at 29.9 V (1000 times lower), and the 1N4121UR-1 specifies 10 nA at 25.1 V. Lower leakage current improves performance in high-impedance circuits and reduces standby power consumption. Both substitutes offer superior leakage characteristics.

Q: Is automotive qualification maintained with the substitute parts?

A: The VLZ33D-GS08 carries AEC-Q101 automotive qualification. The TLZ33D-GS08 does not specify AEC-Q101 qualification in the provided data. The 1N4121UR-1 does not specify automotive qualification. Applications requiring automotive-grade components should confirm qualification status with manufacturers before selection.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message