A3240LLHLT-T Equivalent & Substitute Parts

Part Overview

The A3240LLHLT-T is a unipolar Hall Effect magnetic switch manufactured by Allegro MicroSystems in SOT-23W surface mount packaging. This component functions as a digital switch with open collector output, designed for magnetic field detection applications across industrial and automotive environments. The part is classified as obsolete, making identification of active equivalent and substitute components essential for ongoing design support, production continuity, and new project implementations.

Substiute Parts

A3240LLHLT-T

Allegro MicroSystemsIn Stock: 27462A3240LLHLT-T Datasheet

Current PartRFQ

A1120LLHLX-T

Allegro MicroSystemsIn Stock: 30205A1120LLHLX-T Datasheet

MFR RecommendedRFQ

TLE4946KHTSA1

Infineon TechnologiesIn Stock: 56429TLE4946KHTSA1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the A3240LLHLT-T is determined by the following critical parameters:

Primary Compatibility Criteria:

• Hall Effect technology with South Pole polarization
• Unipolar or latch switch function
• Surface mount packaging (SOT-23W or equivalent footprint)
• Operating temperature range of -40°C to 150°C
• Supply voltage overlap within 4.2V ~ 24V range
• Output collector type (open collector or open drain acceptable)
• Sensing range compatibility (5mT nominal operation)

Identified Substitutes:

1. A1120LLHLX-T (Allegro MicroSystems) - Active product status, same manufacturer family, unipolar switch function, SOT-23W package, South Pole polarization, compatible voltage and temperature ranges.

2. TLE4946KHTSA1 (Infineon Technologies) - Active product status, latch function variant, Hall Effect technology, South Pole polarization, compatible temperature range, open collector output, automotive qualified.

Parameter Comparison

Engineering Selection Recommendations

A1120LLHLX-T Selection Criteria:

• Preferred for direct replacement in existing designs requiring unipolar switch function
• Active product status with established supply chain
• Identical package footprint (SOT-23W) and pinout compatibility
• Automotive grade with AEC-Q100 qualification provides enhanced reliability documentation
• Lower supply current (4mA vs. 6mA) offers improved power efficiency
• Tighter release threshold (0.5mT vs. 5mT) provides enhanced hysteresis control
• Extended lower voltage limit (3V vs. 4.2V) expands application range

TLE4946KHTSA1 Selection Criteria:

• Suitable for applications where latch function is acceptable or preferred over unipolar switching
• Active product status with automotive qualification (AEC-Q100)
• Different package variant (SC-59/SOT-23-3) requires PCB layout verification
• Higher sensing threshold (19mT trip) indicates different magnetic field sensitivity profile
• Temperature compensation feature provides improved performance stability
• Lower maximum output current (20mA vs. 25mA) requires load verification
• Supply voltage range (2.7V ~ 18V) does not fully overlap at upper limit (18V vs. 24V)

Frequently Asked Questions (FAQ)

Q: Can A1120LLHLX-T directly replace A3240LLHLT-T without PCB modifications?

A: Yes. Both components use identical SOT-23W packaging and pinout. No PCB layout changes are required. Electrical parameter differences (supply current, release threshold) are within acceptable tolerance for most applications.

Q: What is the functional difference between unipolar switch and latch function?

A: Unipolar switch (A3240LLHLT-T, A1120LLHLX-T) activates on magnetic field presence and deactivates on field removal. Latch function (TLE4946KHTSA1) requires separate trip and release magnetic field polarities, maintaining output state until opposite polarity is applied.

Q: Is TLE4946KHTSA1 compatible with 24V supply applications?

A: No. TLE4946KHTSA1 maximum supply voltage is 18V, which does not accommodate 24V applications. A1120LLHLX-T supports the full 24V range and is the appropriate selection for 24V systems.

Q: What packaging considerations apply to TLE4946KHTSA1?

A: TLE4946KHTSA1 uses SC-59/SOT-23-3 package variant. While functionally compatible, PCB footprint verification is required as this differs from the SOT-23W package of the main part and A1120LLHLX-T substitute.

Q: Are both substitute parts automotive qualified?

A: Yes. Both A1120LLHLX-T and TLE4946KHTSA1 carry automotive grade designation with AEC-Q100 qualification, providing documented reliability and quality assurance for automotive applications.

Q: How do sensing range differences affect substitution?

A: A1120LLHLX-T maintains the 5mT trip threshold with improved 0.5mT release hysteresis. TLE4946KHTSA1 operates at 19mT trip threshold, requiring significantly stronger magnetic fields. Application magnetic field strength must be verified against the selected substitute.