AP1084D18L-U Equivalent & Substitute Parts

Part Overview

The AP1084D18L-U is a linear voltage regulator IC manufactured by Diodes Incorporated, designed to deliver a fixed 1.8V output at 5A maximum current in a TO-252-3 (DPAK) surface mount package. This device is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity. The regulator incorporates over-current and over-temperature protection features suitable for general-purpose power management applications requiring stable 1.8V rails.

Substiute Parts

AP1084D18L-U

Diodes IncorporatedIn Stock: 1245AP1084D18L-U Datasheet

Current PartRFQ

LD1117ADT18TR

STMicroelectronicsIn Stock: 18206LD1117ADT18TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AP1084D18L-U is determined by the following critical parameters:

• Fixed Output Voltage: 1.8V (exact match required)
• Package Type: TO-252-3 (DPAK) surface mount configuration
• Output Current Capability: Minimum 5A required for direct replacement
• Input Voltage Range: Compatible with 12V maximum input specification
• Protection Features: Over-current and over-temperature protection mandatory
• Operating Temperature: 0°C to 125°C range
• RoHS Compliance: ROHS3 Compliant status

The LD1117ADT18TR from STMicroelectronics shares the same output voltage, package type, and protection feature set. However, this substitute has a reduced maximum output current rating of 1A compared to the 5A specification of the AP1084D18L-U. This difference is a critical limitation that restricts the LD1117ADT18TR to applications requiring lower current delivery.

Parameter Comparison

Engineering Selection Recommendations

The LD1117ADT18TR is suitable as a substitute for the AP1084D18L-U only in applications where the maximum output current requirement does not exceed 1A. Both devices maintain identical output voltage specifications, identical operating temperature ranges, and equivalent protection feature sets. Both are RoHS3 compliant and carry active or legacy product status from established manufacturers.

For applications requiring the full 5A output current capability of the AP1084D18L-U, the LD1117ADT18TR cannot serve as a direct replacement due to its 1A current limitation. In such cases, alternative regulators with matching 5A output current specifications and TO-252-3 packaging must be evaluated.

The LD1117ADT18TR offers the advantage of active product status from STMicroelectronics, ensuring continued availability and manufacturing support compared to the obsolete AP1084D18L-U.

Frequently Asked Questions (FAQ)

Q: Can the LD1117ADT18TR replace the AP1084D18L-U in all applications?

A: No. The LD1117ADT18TR has a maximum output current of 1A, while the AP1084D18L-U is rated for 5A. Substitution is only valid for circuits requiring 1A or less output current at 1.8V.

Q: Are the package types identical between these parts?

A: Yes. Both devices use the TO-252-3 (DPAK) surface mount package with identical pinout and thermal characteristics, allowing direct PCB footprint compatibility.

Q: What is the significance of the product status difference?

A: The AP1084D18L-U is obsolete, meaning Diodes Incorporated no longer manufactures or supports this part. The LD1117ADT18TR is active, indicating STMicroelectronics continues production and provides full technical support.

Q: Do both regulators provide the same protection features?

A: Yes. Both the AP1084D18L-U and LD1117ADT18TR include over-current and over-temperature protection, ensuring equivalent fault response behavior.

Q: Is the input voltage range compatible between these parts?

A: Both devices accept input voltages up to their specified maximums (12V for AP1084D18L-U, 15V for LD1117ADT18TR). The LD1117ADT18TR has a higher input voltage rating, making it compatible with the AP1084D18L-U's 12V specification.

Q: Are there RoHS compliance differences?

A: No. Both parts are ROHS3 compliant, meeting identical environmental and material restriction standards.