AP1117K18L-13 Equivalent & Substitute Parts

Part Overview

The AP1117K18L-13 is a linear voltage regulator IC manufactured by Diodes Incorporated, designed to deliver a fixed 1.8V output at 1A maximum current. This device operates as a positive fixed output regulator in a TO-263-3 (D2PAK) surface mount package. The part is currently classified as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity. Substitute parts must maintain electrical compatibility across output voltage, current capacity, dropout voltage, and thermal performance parameters while accommodating the same or compatible package footprint.

Substiute Parts

AP1117K18L-13

Diodes IncorporatedIn Stock: 12429AP1117K18L-13 Datasheet

Current PartRFQ

LD1086D2T18TR

STMicroelectronicsIn Stock: 16797LD1086D2T18TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AP1117K18L-13 is determined by strict alignment of the following electrical and mechanical parameters:

Critical Substitution Criteria:

• Fixed output voltage of 1.8V
• Output current rating equal to or greater than 1A
• Maximum input voltage of 18V or higher
• Dropout voltage performance compatible with system design
• Identical or pin-compatible package (TO-263-3 / D2PAK)
• Surface mount mounting type
• Over current and over temperature protection features
• RoHS3 compliance

The LD1086D2T18TR from STMicroelectronics meets all substitution requirements. This part maintains the 1.8V fixed output voltage and D2PAK package compatibility while offering enhanced electrical performance characteristics, including higher output current capacity (1.5A), higher maximum input voltage (30V), and improved PSRR (82dB at 120Hz). The LD1086D2T18TR is classified as active product status, ensuring continued availability and manufacturing support.

Parameter Comparison

Engineering Selection Recommendations

The LD1086D2T18TR is the qualified substitute for the obsolete AP1117K18L-13. Both parts maintain ROHS3 compliance and unlimited moisture sensitivity classification, ensuring regulatory and environmental compatibility. The substitute part offers active product status with ongoing manufacturer support, addressing the obsolescence of the original component.

The LD1086D2T18TR provides enhanced electrical performance with higher output current capacity (1.5A versus 1A), extended maximum input voltage rating (30V versus 18V), and superior power supply rejection ratio (82dB versus 60dB). These improvements ensure the substitute operates within or exceeds the electrical requirements of designs originally specified for the AP1117K18L-13.

Both parts employ identical D2PAK package geometry and pin configuration, enabling direct PCB footprint compatibility without layout modifications. The substitute maintains the same quiescent current specification (10 mA) and protection feature set (over current and over temperature), preserving thermal and current management behavior in the target application.

Frequently Asked Questions (FAQ)

Q: Can the LD1086D2T18TR be used as a direct replacement for the AP1117K18L-13?

A: Yes. Both parts feature identical 1.8V fixed output voltage, D2PAK package configuration, and pin compatibility. The LD1086D2T18TR can be substituted without PCB layout changes or design modifications.

Q: What are the key differences between these two regulators?

A: The LD1086D2T18TR offers higher output current capacity (1.5A versus 1A), higher maximum input voltage (30V versus 18V), improved PSRR performance (82dB versus 60dB), and extended operating temperature range (-40°C to 125°C versus 0°C to 125°C). The substitute is active product status while the original is obsolete.

Q: Are there any package compatibility concerns?

A: No. Both parts use the TO-263-3 D2PAK package with identical lead spacing and thermal tab configuration. Existing PCB designs require no modification.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the AP1117K18L-13 and LD1086D2T18TR are ROHS3 compliant with MSL 1 (unlimited) moisture sensitivity rating. REACH status is unaffected for both parts.

Q: What is the impact of the higher output current rating on thermal design?

A: The LD1086D2T18TR's 1.5A rating provides additional current headroom. Thermal performance depends on junction temperature, which is influenced by input-output voltage differential, load current, and PCB thermal design. Both parts employ identical thermal management through the D2PAK tab.

Q: Can the LD1086D2T18TR handle higher input voltages than the original part?

A: Yes. The LD1086D2T18TR supports maximum input voltage of 30V compared to 18V for the AP1117K18L-13. This extended rating provides design flexibility for applications with higher supply voltages.