AISC-1812H-3R9N-T Equivalent & Substitute Parts

Part Overview

The AISC-1812H-3R9N-T is a 3.9 µH unshielded drum core wirewound inductor manufactured by Abracon LLC in 1812 (4532 Metric) surface mount package. This component is rated for 780 mA continuous current with 150mOhm maximum DC resistance and operates across -25°C to 85°C. The part is currently obsolete, necessitating identification of functionally equivalent alternatives that maintain electrical and mechanical compatibility for new designs or production continuity.

Substiute Parts

AISC-1812H-3R9N-T

Abracon LLCIn Stock: 1153AISC-1812H-3R9N-T Datasheet

Current PartRFQ

7440450039

Würth ElektronikIn Stock: 22917440450039 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AISC-1812H-3R9N-T is determined by the following critical parameters:

• Inductance Value: Must be 3.9 µH to maintain circuit performance
• Package / Case: Must be 1812 (4532 Metric) for mechanical and PCB layout compatibility
• Core Type: Must be ferrite, unshielded drum core to preserve electromagnetic characteristics
• Mounting Type: Must be surface mount for assembly process compatibility
• Current Rating: Must meet or exceed 780 mA to handle circuit load requirements
• DC Resistance: Must not exceed 150mOhm to maintain power efficiency specifications

The substitute part 7440450039 (Würth Elektronik WE-LQ series) satisfies all critical substitution criteria while offering enhanced electrical performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The 7440450039 (Würth Elektronik WE-LQ series) is a direct functional equivalent for the obsolete AISC-1812H-3R9N-T. Both components maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment. The substitute part is actively manufactured, providing supply chain continuity and long-term availability.

The substitute demonstrates superior electrical performance: current rating of 1.32 A exceeds the original 780 mA requirement, DC resistance of 140mOhm Max meets the 150mOhm specification, and inductance tolerance of ±20% is tighter than the original ±30%. Operating temperature range extends to -40°C ~ 125°C, providing broader environmental coverage than the original -25°C ~ 85°C specification.

Physical compatibility is maintained across all critical dimensions. The substitute height of 0.114" (2.90mm) represents a 0.004" (0.10mm) increase over the original 0.110" (2.80mm), which remains within typical PCB assembly tolerances for 1812 package components. Identical footprint dimensions (0.177" L x 0.126" W / 4.50mm x 3.20mm) ensure direct PCB layout compatibility without redesign.

Frequently Asked Questions (FAQ)

Q: Can the 7440450039 be used as a direct replacement for the AISC-1812H-3R9N-T?

A: Yes. Both components share identical inductance value (3.9 µH), package type (1812 / 4532 Metric), core construction (ferrite unshielded drum core), and mounting method (surface mount). The substitute meets or exceeds all electrical requirements of the original part.

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

A: The substitute offers enhanced specifications: higher current rating (1.32 A vs 780 mA), lower DC resistance (140mOhm vs 150mOhm), tighter inductance tolerance (±20% vs ±30%), wider operating temperature range (-40°C ~ 125°C vs -25°C ~ 85°C), and higher self-resonant frequency (54 MHz vs 41 MHz). Physical height increases by 0.004" (0.10mm).

Q: Will the 0.004" height difference affect PCB assembly?

A: No. The 0.004" (0.10mm) height increase from 2.80mm to 2.90mm remains within standard PCB assembly tolerances for 1812 surface mount components and does not require design modifications.

Q: Are both parts RoHS and REACH compliant?

A: Yes. Both the AISC-1812H-3R9N-T and 7440450039 are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements.

Q: What is the supply status of each part?

A: The AISC-1812H-3R9N-T is obsolete with limited remaining inventory (1094 pcs). The 7440450039 is actively manufactured by Würth Elektronik with current inventory of 2200 pcs, ensuring long-term availability for production requirements.

Q: Are the inductance tolerances compatible for circuit design?

A: Yes. The substitute's ±20% tolerance is tighter than the original ±30%, providing improved consistency. Circuits designed for the original ±30% tolerance will operate within specification with the substitute part.