DL4751A-TP Equivalent & Substitute Parts

Part Overview

The DL4751A-TP is a Zener diode rated at 30 V, 1 W with ±5% tolerance, manufactured by Micro Commercial Co in a surface mount MELF (DO-213AB) package. This component is classified as obsolete, necessitating identification of active equivalent alternatives for new designs and ongoing production requirements. Substitute parts must maintain identical electrical specifications while accommodating different package formats and manufacturer sourcing options.

Key Parameters

Parameter	Value
Voltage - Zener (Nom)	30 V
Tolerance	±5%
Power - Max	1 W
Impedance (Max)	40 Ohms
Current - Reverse Leakage @ Vr	5 µA @ 22.8 V
Voltage - Forward (Vf) (Max)	1.2 V @ 200 mA
Operating Temperature Range	-65°C ~ 175°C
Mounting Type	Surface Mount
Package / Case	DO-213AB, MELF
RoHS Status	ROHS3 Compliant
Moisture Sensitivity Level	1 (Unlimited)

Substitute Part Grouping Explanation

Substitution of the DL4751A-TP is determined by strict equivalence across the following electrical parameters: nominal Zener voltage (30 V), power rating (1 W), tolerance (±5%), impedance maximum (40 Ohms), reverse leakage current (5 µA @ 22.8 V), and forward voltage (1.2 V @ 200 mA). All substitute parts must be surface mount Zener diodes with identical electrical characteristics and compliance certifications (ROHS3, REACH Unaffected, EAR99).

Substitutes are grouped into two categories based on package format:

Category 1: MELF Package (DO-213AB) – Direct mechanical and electrical equivalents maintaining the original package footprint.

Category 2: SMA Package (DO-214AC) – Electrical equivalents with alternative surface mount package format, requiring PCB layout modification.

Parameter Comparison

Parameter	DL4751A-TP	SMAJ4751A-TP	1N4751AUR/TR
Manufacturer	Micro Commercial Co	Micro Commercial Co	Microchip Technology
Voltage - Zener (Nom)	30 V	30 V	30 V
Tolerance	±5%	±5%	±5%
Power - Max	1 W	1 W	1 W
Impedance (Max)	40 Ohms	40 Ohms	40 Ohms
Current - Reverse Leakage @ Vr	5 µA @ 22.8 V	5 µA @ 22.8 V	5 µA @ 22.8 V
Voltage - Forward (Vf) (Max)	1.2 V @ 200 mA	1.2 V @ 100 mA	1.2 V @ 200 mA
Operating Temperature Range	-65°C ~ 175°C	-65°C ~ 150°C	-65°C ~ 175°C
Mounting Type	Surface Mount	Surface Mount	Surface Mount
Package / Case	DO-213AB, MELF	DO-214AC, SMA	DO-213AB, MELF
Product Status	Obsolete	Active	Active
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant
REACH Status	REACH Unaffected	REACH Unaffected	REACH Unaffected

Engineering Selection Recommendations

1N4751AUR/TR (Microchip Technology) is the primary substitute for direct replacement applications. This part maintains identical package format (DO-213AB, MELF), electrical specifications, and operating temperature range (-65°C ~ 175°C). Product status is active with confirmed inventory availability (839 Pcs). This substitute requires no PCB layout modification and provides full parametric equivalence.

SMAJ4751A-TP (Micro Commercial Co) serves as an alternative for applications where SMA package format (DO-214AC) is acceptable. This part maintains all critical electrical parameters but operates within a reduced temperature range (-65°C ~ 150°C) and specifies forward voltage at 100 mA rather than 200 mA. Product status is active with inventory availability (753 Pcs). PCB layout modification is required due to package format change.

Both substitutes carry ROHS3 compliance and REACH Unaffected status, matching the original part's regulatory certifications.

Frequently Asked Questions (FAQ)

Q: Can SMAJ4751A-TP replace DL4751A-TP in all applications?

A: SMAJ4751A-TP provides electrical equivalence for the 30 V, 1 W Zener function. However, the operating temperature range is reduced to -65°C ~ 150°C (versus -65°C ~ 175°C for DL4751A-TP). Applications requiring operation above 150°C require 1N4751AUR/TR. Additionally, the SMA package (DO-214AC) differs from the MELF package (DO-213AB), necessitating PCB layout modification.

Q: What is the difference between DO-213AB (MELF) and DO-214AC (SMA) packages?

A: DO-213AB (MELF) and DO-214AC (SMA) are distinct surface mount package formats with different footprints, lead configurations, and PCB pad layouts. Direct mechanical substitution between these packages is not possible without PCB redesign. 1N4751AUR/TR maintains the DO-213AB format for direct substitution, while SMAJ4751A-TP uses DO-214AC format.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. Both 1N4751AUR/TR and SMAJ4751A-TP are ROHS3 compliant and REACH unaffected, matching the original DL4751A-TP specifications.

Q: What is the significance of the forward voltage specification difference?

A: DL4751A-TP and 1N4751AUR/TR specify forward voltage at 200 mA (1.2 V max), while SMAJ4751A-TP specifies forward voltage at 100 mA (1.2 V max). This difference reflects measurement conditions rather than functional capability. Both values remain within acceptable Zener diode forward voltage parameters for 30 V devices.

Q: Which substitute should be selected for new designs?

A: For new designs requiring the MELF package format, 1N4751AUR/TR is the recommended substitute, providing full parametric equivalence and active product status. For designs where SMA package format is preferred or required, SMAJ4751A-TP is suitable, provided the reduced operating temperature range (-65°C ~ 150°C) meets application requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message