A3958SLBTR-T Equivalent & Substitute Parts

Part Overview

The A3958SLBTR-T is a motor driver IC manufactured by Allegro MicroSystems, designed for brushed DC motor applications. This device integrates control and power stage functionality in a 24-SOIC package with a supply voltage range of 4.5V to 5.5V and load voltage capability of 20V to 50V. The part is classified as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity.

Substiute Parts

A3958SLBTR-T

Allegro MicroSystemsIn Stock: 1495A3958SLBTR-T Datasheet

Current PartRFQ

A3959SLBTR-T

Allegro MicroSystemsIn Stock: 18690A3959SLBTR-T Datasheet

MFR RecommendedRFQ

L6229DTR

STMicroelectronicsIn Stock: 2788L6229DTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the A3958SLBTR-T is determined by the following critical parameters:

Primary Compatibility Criteria:

• Package / Case: 24-SOIC form factor (0.295", 7.50mm Width)
• Mounting Type: Surface Mount
• Function: Fully Integrated Driver with Control and Power Stage
• Motor Type: Brushed DC or compatible motor control capability
• Output Configuration: Half Bridge topology

Secondary Compatibility Criteria:

• Voltage - Supply: Must accommodate 4.5V ~ 5.5V input range
• Voltage - Load: Must support 20V ~ 50V load voltage range
• Current - Output: Minimum 2A capability
• Interface: Serial or Parallel control interface
• Technology: DMOS or equivalent semiconductor technology

The A3959SLBTR-T qualifies as a direct manufacturer-recommended substitute, sharing identical package, supply voltage, load voltage range, and DMOS technology. The L6229DTR represents an alternative substitute with different motor type capability (BLDC) and modified electrical specifications, suitable only for applications where voltage and current requirements align with its 12V ~ 52V supply range and 1.4A output current.

Parameter Comparison

Engineering Selection Recommendations

A3959SLBTR-T (Primary Substitute): The A3959SLBTR-T is the manufacturer-recommended substitute for the A3958SLBTR-T. Both devices share identical supply voltage (4.5V ~ 5.5V), load voltage range (9.5V ~ 50V minimum compatibility), package form factor (24-SOIC), and DMOS technology. The A3959SLBTR-T offers increased output current capability (3A versus 2A) and maintains active product status with ROHS3 compliance. The primary design difference is the parallel control interface versus serial interface on the original part, requiring firmware or control circuit modification. This substitute is suitable for direct replacement in applications where control interface adaptation is feasible.

L6229DTR (Alternative Substitute): The L6229DTR is an active STMicroelectronics product with ROHS3 compliance, suitable only for applications requiring BLDC motor control capability. This device operates across a wider supply voltage range (12V ~ 52V) and is not compatible with the 4.5V ~ 5.5V supply specification of the A3958SLBTR-T. The L6229DTR features a three-phase half-bridge output configuration versus the two-phase configuration of the original part. Selection of this substitute requires complete system redesign and is applicable only to BLDC motor applications with compatible voltage requirements.

Frequently Asked Questions (FAQ)

Q: Can the A3959SLBTR-T directly replace the A3958SLBTR-T without circuit modification?

A: The A3959SLBTR-T shares identical package, supply voltage, and load voltage specifications. However, the control interface differs (parallel versus serial), requiring modification to the control circuit or firmware. Pin-level compatibility must be verified against the respective datasheets before implementation.

Q: What is the primary limitation of using the L6229DTR as a substitute?

A: The L6229DTR operates at 12V ~ 52V supply voltage, which is incompatible with the A3958SLBTR-T's 4.5V ~ 5.5V supply specification. Additionally, the L6229DTR is designed for BLDC motor control, not brushed DC applications. This substitute is applicable only to systems with BLDC motor requirements and compatible voltage supplies.

Q: Are all three parts available in the same package form factor?

A: Yes, all three parts are available in 24-SOIC (0.295", 7.50mm Width) surface mount packages. Physical PCB footprint compatibility is maintained across all three devices.

Q: What is the current output capability difference between the A3958SLBTR-T and A3959SLBTR-T?

A: The A3958SLBTR-T provides 2A output current, while the A3959SLBTR-T provides 3A output current. Applications requiring higher motor drive current may benefit from the increased capability of the A3959SLBTR-T.

Q: Which substitute is recommended for new designs?

A: The A3959SLBTR-T is the manufacturer-recommended substitute and maintains active product status. For applications requiring brushed DC motor control at 4.5V ~ 5.5V supply voltage, the A3959SLBTR-T is the appropriate selection, provided control interface requirements can be accommodated.

Q: Are there temperature operating range differences between the substitutes?

A: The A3958SLBTR-T and A3959SLBTR-T both operate across -20°C ~ 150°C (TJ). The L6229DTR operates across -25°C ~ 125°C (TJ), providing lower maximum junction temperature capability.