A3280LUA-T Equivalent & Substitute Parts

Part Overview

The A3280LUA-T is a digital switch latch Hall Effect magnetic sensor manufactured by Allegro MicroSystems, housed in a 3-SIP package. This component functions as an open collector magnetic switch with south pole polarization, designed for applications requiring latching behavior in response to magnetic field detection. The product is currently obsolete, making identification of compatible substitute components essential for ongoing system support and new design implementations.

Substiute Parts

A3280LUA-T

Allegro MicroSystemsIn Stock: 3367A3280LUA-T Datasheet

Current PartRFQ

A1220LUA-T

Allegro MicroSystemsIn Stock: 48971A1220LUA-T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The A1220LUA-T qualifies as a direct substitute for the A3280LUA-T based on the following critical parameters:

• Hall Effect Technology: Both components utilize Hall Effect sensing with identical south pole polarization and matching 4mT trip / -4mT release thresholds
• Latching Function: Both devices implement latch-mode operation
• Package Compatibility: Both use 3-SSIP through-hole packaging, ensuring mechanical and pin-level compatibility
• Operating Temperature Range: Identical -40°C to 150°C specification
• Output Current Rating: Both support 25mA maximum output current
• Supply Voltage Compatibility: A1220LUA-T operates within 3V–24V, which encompasses the A3280LUA-T range of 4.2V–24V
• Compliance Standards: Both are ROHS3 compliant with REACH unaffected status

The A1220LUA-T represents an active product with automotive-grade qualification (AEC-Q100), providing enhanced availability and long-term supply assurance compared to the obsolete A3280LUA-T.

Parameter Comparison

Engineering Selection Recommendations

The A1220LUA-T is the designated manufacturer-recommended substitute for the obsolete A3280LUA-T. Selection of the A1220LUA-T provides the following advantages:

• Active Product Status: The A1220LUA-T maintains active production status with significantly higher inventory availability (48,942 pcs vs. 3,312 pcs), ensuring long-term supply continuity
• Automotive Qualification: AEC-Q100 qualification provides additional reliability assurance for mission-critical applications
• Electrical Compatibility: Identical sensing thresholds, output current ratings, and temperature range ensure functional equivalence in existing circuit designs
• Lower Supply Current: The A1220LUA-T requires 4mA maximum supply current compared to 8mA for the A3280LUA-T, reducing power consumption
• Extended Voltage Range: The lower minimum supply voltage (3V vs. 4.2V) expands application flexibility for low-voltage systems
• Regulatory Compliance: Both components meet ROHS3 and REACH requirements

The primary design consideration is the output stage difference: the A3280LUA-T uses open collector output while the A1220LUA-T uses open drain output. Both topologies are functionally equivalent in standard pull-up resistor configurations and do not require circuit modifications for substitution.

Frequently Asked Questions (FAQ)

Q: Can the A1220LUA-T directly replace the A3280LUA-T without circuit modifications?

A: Yes. Both components share identical package geometry (3-SSIP), pin configuration, sensing thresholds (4mT trip / -4mT release), output current rating (25mA), and operating temperature range (-40°C to 150°C). The open collector/open drain output difference does not require circuit changes in standard pull-up resistor implementations.

Q: What is the difference between open collector and open drain outputs?

A: Both output types function identically in practical applications with pull-up resistors. Open collector refers to bipolar transistor output stages, while open drain refers to MOSFET output stages. The functional behavior and circuit requirements are equivalent.

Q: Is the A1220LUA-T suitable for automotive applications?

A: Yes. The A1220LUA-T carries AEC-Q100 automotive qualification, making it suitable for automotive-grade applications. The A3280LUA-T does not specify automotive qualification.

Q: What is the impact of the lower supply current requirement in the A1220LUA-T?

A: The A1220LUA-T requires 4mA maximum supply current versus 8mA for the A3280LUA-T. This 50% reduction in supply current decreases power dissipation and thermal load, beneficial for battery-powered or thermally constrained applications.

Q: Are there any voltage supply considerations when substituting?

A: The A1220LUA-T operates across 3V–24V, which fully encompasses the A3280LUA-T range of 4.2V–24V. Systems operating above 4.2V experience no voltage-related constraints. Systems operating between 3V and 4.2V can utilize the A1220LUA-T but could not use the original A3280LUA-T.

Q: Do both parts meet environmental and regulatory compliance requirements?

A: Yes. Both the A3280LUA-T and A1220LUA-T are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory standards.