A3940KLPTR-T Equivalent & Substitute Parts

Part Overview

The A3940KLPTR-T is a motor driver IC manufactured by Allegro MicroSystems, designed for brushed DC motor control applications. This device integrates power MOSFET technology in a 28-TSSOP package with exposed pad, supporting supply voltages from 7V to 40V and operating temperatures from -40°C to 135°C. The part is classified as Obsolete, making identification of suitable alternatives essential for ongoing system support and new design implementations.

Substiute Parts

A3940KLPTR-T

Allegro MicroSystemsIn Stock: 25434A3940KLPTR-T Datasheet

Current PartRFQ

A3941KLPTR-T

Allegro MicroSystemsIn Stock: 25535A3941KLPTR-T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the A3940KLPTR-T is determined by strict alignment of the following critical parameters:

Mandatory Compatibility Criteria:

• Package type: 28-TSSOP with exposed pad (physical and electrical compatibility)
• Motor control function: Brushed DC motor driver with commutation and direction management
• Output configuration: Pre-Driver Half Bridge (2) topology
• Technology: Power MOSFET-based implementation
• Automotive grade classification
• RoHS3 compliance

Allowable Parameter Variations:

• Supply voltage range: The substitute may support an extended or overlapping voltage window, provided the original operating range (7V-40V) remains fully supported
• Operating temperature range: The substitute may support an extended temperature window
• Interface type: May differ (Parallel vs. PWM) if functional equivalence is maintained for the application
• Moisture sensitivity level: May vary within automotive-grade specifications

The A3941KLPTR-T qualifies as a direct substitute based on these criteria.

Parameter Comparison

Engineering Selection Recommendations

The A3941KLPTR-T is the manufacturer-recommended substitute for the obsolete A3940KLPTR-T. Both devices maintain identical package geometry, motor control topology, and automotive-grade qualification. The A3941KLPTR-T offers extended supply voltage range (5.5V-50V vs. 7V-40V) and higher maximum operating temperature (150°C vs. 135°C), providing enhanced operational flexibility. The interface change from Parallel to PWM represents a functional enhancement rather than a limitation, as PWM control is standard in modern motor driver applications. Both parts maintain ROHS3 compliance and are suitable for automotive applications. The A3941KLPTR-T's Active product status ensures long-term availability and supply chain continuity.

Frequently Asked Questions (FAQ)

Q: Can the A3941KLPTR-T directly replace the A3940KLPTR-T in existing designs?

A: Yes. Both devices share identical 28-TSSOP package geometry, motor control function, output configuration, and automotive-grade specifications. The A3941KLPTR-T's extended voltage and temperature ranges provide backward compatibility with the original design envelope.

Q: What is the significance of the interface change from Parallel to PWM?

A: The interface parameter describes the control signal methodology. PWM (Pulse Width Modulation) is the standard control interface for modern motor drivers and provides equivalent functional capability for commutation and direction management as the Parallel interface.

Q: Are there any moisture sensitivity considerations for long-term storage?

A: The A3940KLPTR-T has MSL 1 (Unlimited shelf life), while the A3941KLPTR-T has MSL 2 (1-year shelf life under controlled conditions). For applications requiring extended storage, standard moisture-barrier packaging practices apply to the A3941KLPTR-T.

Q: Do both parts meet automotive compliance requirements?

A: Yes. Both the A3940KLPTR-T and A3941KLPTR-T are classified as Automotive grade and are ROHS3 compliant, meeting automotive industry standards.

Q: What is the practical impact of the supply voltage range difference?

A: The A3941KLPTR-T supports 5.5V-50V versus the A3940KLPTR-T's 7V-40V. The A3941KLPTR-T's lower minimum voltage (5.5V) and higher maximum voltage (50V) provide extended system design flexibility while maintaining full compatibility with the original 7V-40V operating window.