DL4738A-TP Equivalent & Substitute Parts

Part Overview

The DL4738A-TP is a Zener diode rated at 8.2 V with 1 W power dissipation in a surface mount MELF (DO-213AB) package. This component is classified as obsolete, which necessitates identification of equivalent substitute parts for ongoing design support and procurement. The DL4738A-TP remains available in inventory; however, obsolete status indicates discontinued manufacturing and potential future supply constraints. Substitute parts must maintain electrical equivalence across voltage regulation, power handling, and thermal characteristics while accommodating alternative package formats.

Substiute Parts

DL4738A-TP

Micro Commercial CoIn Stock: 914DL4738A-TP Datasheet

Current PartRFQ

SMAJ4738A-TP

Micro Commercial CoIn Stock: 9337SMAJ4738A-TP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DL4738A-TP is determined by strict equivalence across the following electrical and mechanical parameters:

Electrical Equivalence Criteria:

• Zener voltage: 8.2 V nominal
• Tolerance: ±5%
• Maximum power dissipation: 1 W
• Impedance (Max): 4.5 Ohms
• Reverse leakage current: 10 µA @ 6 V
• Forward voltage: 1.2 V maximum

Mechanical & Compliance Criteria:

• Surface mount technology
• RoHS3 compliance
• Moisture sensitivity level: 1 (Unlimited)
• REACH unaffected status

The SMAJ4738A-TP qualifies as a direct electrical substitute, maintaining all critical zener parameters while utilizing an alternative surface mount package format (DO-214AC/SMA). Both components share identical base product specifications and regulatory compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The SMAJ4738A-TP is the qualified substitute for the DL4738A-TP based on the following engineering criteria:

Electrical Compatibility: All critical zener diode parameters are identical, including nominal voltage, tolerance, power rating, impedance, and leakage characteristics. Forward voltage specifications are equivalent within the stated test conditions.

Regulatory Compliance: Both components maintain ROHS3 compliance and REACH unaffected status, ensuring compatibility with current environmental and safety standards.

Product Status Advantage: The SMAJ4738A-TP carries active product status with significantly higher inventory availability (9,288 units versus 847 units), providing superior long-term supply security compared to the obsolete DL4738A-TP.

Thermal Consideration: The SMAJ4738A-TP operates across -65°C to 150°C, which covers the majority of industrial and commercial temperature ranges. Applications requiring operation above 150°C must evaluate thermal requirements against the DL4738A-TP's extended -65°C to 175°C range.

Package Format: The transition from MELF (DO-213AB) to SMA (DO-214AC) requires PCB layout modification. Both packages are standard surface mount formats with established manufacturing processes.

Frequently Asked Questions (FAQ)

Q: Can SMAJ4738A-TP directly replace DL4738A-TP without circuit modification?

A: Electrical substitution is direct. The zener voltage, power rating, impedance, and leakage characteristics are identical. PCB layout modification is required due to package format differences (MELF to SMA).

Q: What is the primary difference between these two parts?

A: The DL4738A-TP uses a MELF (DO-213AB) package, while the SMAJ4738A-TP uses an SMA (DO-214AC) package. Both are surface mount formats with different footprints and land patterns.

Q: Are there temperature range limitations with the SMAJ4738A-TP?

A: The SMAJ4738A-TP operates from -65°C to 150°C, compared to the DL4738A-TP range of -65°C to 175°C. For applications requiring sustained operation above 150°C, thermal performance must be evaluated against design specifications.

Q: Why is the DL4738A-TP classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. The SMAJ4738A-TP, with active product status and higher inventory levels, provides continuity for ongoing designs and future procurement.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the DL4738A-TP and SMAJ4738A-TP are ROHS3 compliant with moisture sensitivity level 1 (unlimited). REACH status is unaffected for both components.

Q: What packaging format is supplied for the SMAJ4738A-TP?

A: The SMAJ4738A-TP is supplied in Tape & Reel (TR) format, standard for high-volume surface mount assembly operations.

Q: Are the forward voltage specifications identical?

A: Both components specify 1.2 V maximum forward voltage. The DL4738A-TP is tested at 200 mA, while the SMAJ4738A-TP is tested at 100 mA. The maximum specification remains equivalent.