1N4748AH Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N4748AH is a 22 V, 1 W through-hole zener diode manufactured by Taiwan Semiconductor Corporation in DO-204AL (DO-41) axial package. This component is classified as an active product with AEC-Q101 automotive qualification and ROHS3 compliance. Substitute parts are identified based on matching electrical specifications, package compatibility, and operational parameters. Alternative models become necessary when the primary part experiences supply constraints, inventory limitations, or when design requirements permit operation within the specified parameter tolerances of equivalent devices.

Key Parameters

Parameter	Value	Unit
Voltage - Zener (Nom)	22	V
Tolerance	±5%	-
Power - Max	1	W
Impedance (Max)	23	Ohms
Current - Reverse Leakage @ Vr	5	µA @ 16.7 V
Operating Temperature	-55°C ~ 150°C	TJ
Mounting Type	Through Hole	-
Package / Case	DO-204AL, DO-41, Axial	-
RoHS Status	ROHS3 Compliant	-
Grade	Automotive	-
Qualification	AEC-Q101	-

Substitute Part Grouping Explanation

Substitution eligibility for the 1N4748AH is determined by the following critical parameters:

Primary Matching Criteria:

Zener voltage: 22 V nominal with ±5% tolerance
Package compatibility: DO-204AL, DO-41, or axial through-hole equivalents
Mounting type: Through hole
RoHS compliance status

Secondary Compatibility Factors:

Power rating: 1 W or greater
Impedance (Max): 23 Ohms or lower
Reverse leakage current: 5 µA @ 16.7 V or lower
Operating temperature range: Must encompass or exceed -55°C to 150°C

Substitute parts are grouped into two categories based on power dissipation capability:

Category A - Direct 1 W Equivalents: Parts with 1 W power rating and identical electrical specifications. These provide direct functional replacement with no thermal design modifications required.

Category B - Enhanced Performance Substitutes: Parts with power ratings exceeding 1 W (1.3 W or 2 W). These provide superior thermal performance and lower impedance characteristics while maintaining the same zener voltage and tolerance specifications. Enhanced performance substitutes are suitable for applications where thermal margin or lower impedance is beneficial.

Parameter Comparison

Part Number	Manufacturer	Vz (Nom)	Tolerance	Power (Max)	Zzt (Max)	Ir @ Vr	Temp Range	Package	RoHS	AEC-Q101
1N4748AH	Taiwan Semiconductor	22 V	±5%	1 W	23 Ω	5 µA @ 16.7 V	-55°C ~ 150°C	DO-204AL	ROHS3	Yes
1N4748A	Lumimax Optoelectronic	22 V	±5%	1 W	23 Ω	5 µA @ 16.7 V	-65°C ~ 200°C	DO-41G	RoHS	No
1N4748A-T50A	onsemi	22 V	±5%	1 W	23 Ω	5 µA @ 16.7 V	-65°C ~ 200°C	DO-41	ROHS3	No
1N4748A-TR	Vishay General Semiconductor	22 V	±5%	1.3 W	23 Ω	5 µA @ 16.7 V	-55°C ~ 175°C	DO-204AL	ROHS3	Yes
1N4748ATR	onsemi	22 V	±5%	1 W	23 Ω	5 µA @ 16.7 V	-65°C ~ 200°C	DO-41	ROHS3	No
2EZ22D5	Microsemi Corporation	22 V	±5%	2 W	12 Ω	500 nA @ 16.7 V	-65°C ~ 150°C	DO-204AL	ROHS3	No
2EZ22D5-TP	Micro Commercial Co	22 V	±5%	2 W	12 Ω	500 nA @ 16.7 V	-55°C ~ 150°C	DO-41	ROHS3	No

Engineering Selection Recommendations

Direct Replacement (1 W Category):

The 1N4748A-TR manufactured by Vishay General Semiconductor provides the closest functional equivalence to the 1N4748AH. Both parts share identical zener voltage (22 V), tolerance (±5%), impedance (23 Ω), and reverse leakage specifications. The 1N4748A-TR maintains AEC-Q101 automotive qualification and ROHS3 compliance. The enhanced power rating (1.3 W versus 1 W) provides additional thermal margin without requiring circuit modifications. Operating temperature range (-55°C to 175°C) encompasses the primary part specification.

The 1N4748ATR and 1N4748A-T50A from onsemi are electrically equivalent 1 W devices with matching zener voltage and impedance. Both maintain ROHS3 compliance. The 1N4748ATR offers extended operating temperature range (-65°C to 200°C) and higher inventory availability (21,963 units). Neither part carries AEC-Q101 qualification.

The 1N4748A from Lumimax Optoelectronic matches all critical electrical parameters with 1 W power rating and 23 Ω impedance. Extended operating temperature range (-65°C to 200°C) is provided. RoHS compliance is confirmed without ROHS3 designation. AEC-Q101 qualification is not applicable.

Enhanced Performance Substitutes (2 W Category):

The 2EZ22D5 from Microsemi Corporation and 2EZ22D5-TP from Micro Commercial Co provide superior performance characteristics with 2 W power dissipation and reduced impedance (12 Ω). Both maintain 22 V zener voltage and ±5% tolerance. Reverse leakage current is significantly lower (500 nA versus 5 µA). ROHS3 compliance is confirmed for both parts. These devices are suitable for applications where thermal performance or lower impedance is advantageous. Neither part carries AEC-Q101 qualification.

Compliance Considerations:

For applications requiring AEC-Q101 automotive qualification, the 1N4748A-TR is the only substitute that maintains this certification. The primary part 1N4748AH and the 1N4748A-TR both satisfy automotive-grade requirements.

All identified substitutes maintain ROHS3 or RoHS compliance, ensuring environmental regulatory alignment with the primary part.

Frequently Asked Questions (FAQ)

Q: Can the 1N4748A-TR replace the 1N4748AH in automotive applications?

A: Yes. The 1N4748A-TR maintains AEC-Q101 automotive qualification and ROHS3 compliance identical to the 1N4748AH. Electrical specifications are matched: 22 V zener voltage, ±5% tolerance, 23 Ω impedance, and 5 µA reverse leakage. The enhanced 1.3 W power rating provides additional thermal margin. Operating temperature range (-55°C to 175°C) encompasses the primary part specification.

Q: What is the difference between 1 W and 2 W zener diodes in this voltage class?

A: Power rating indicates maximum continuous power dissipation capability. The 1 W devices (1N4748AH, 1N4748A, 1N4748A-T50A, 1N4748ATR) are suitable for applications with lower current requirements. The 2 W devices (2EZ22D5, 2EZ22D5-TP) accommodate higher current loads and provide superior thermal performance. The 2 W devices also feature lower impedance (12 Ω versus 23 Ω), resulting in tighter voltage regulation characteristics.

Q: Are all substitute parts compatible with the DO-41 package footprint?

A: Yes. All identified substitute parts utilize DO-204AL, DO-41, or equivalent axial through-hole packages. These packages are mechanically and electrically interchangeable for PCB mounting. Specific package designations (DO-41G, DO-41, DO-204AL) represent manufacturer nomenclature variations for the same physical form factor.

Q: Which substitute offers the best thermal performance?

A: The 2 W devices (2EZ22D5 and 2EZ22D5-TP) provide superior thermal performance with doubled power dissipation capacity and reduced impedance (12 Ω). These characteristics enable operation at higher current levels with lower junction temperature rise. The 1N4748A-TR offers intermediate thermal improvement with 1.3 W rating while maintaining automotive qualification.

Q: Do all substitutes maintain the same reverse leakage specification?

A: No. The 1 W devices (1N4748AH, 1N4748A, 1N4748A-T50A, 1N4748ATR) specify 5 µA reverse leakage at 16.7 V. The 2 W devices (2EZ22D5, 2EZ22D5-TP) specify significantly lower reverse leakage of 500 nA at 16.7 V. Lower reverse leakage improves circuit performance in high-impedance applications.

Q: Is AEC-Q101 qualification required for all applications?

A: AEC-Q101 qualification is required for automotive-grade applications. The 1N4748AH and 1N4748A-TR both carry this certification. For non-automotive applications, all identified substitutes provide equivalent electrical performance without this qualification requirement.

Q: What is the operating temperature difference between substitutes?

A: The primary part 1N4748AH operates from -55°C to 150°C. The 1N4748A-TR operates from -55°C to 175°C. The 1N4748A, 1N4748A-T50A, and 1N4748ATR extend to -65°C to 200°C. The 2EZ22D5 operates from -65°C to 150°C. The 2EZ22D5-TP operates from -55°C to 150°C. Selection depends on specific thermal environment requirements.

Q: Can 1 W and 2 W devices be used interchangeably?

A: Yes, within the circuit design constraints. The 2 W devices are physically compatible and electrically equivalent at the 22 V zener voltage specification. However, the 2 W devices feature lower impedance (12 Ω versus 23 Ω), which affects voltage regulation characteristics. Circuit performance may differ slightly due to impedance variation. Verification of circuit behavior is necessary if impedance-sensitive applications are involved.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message