A3966SA Equivalent & Substitute Parts

Part Overview

The A3966SA is a bipolar motor driver IC manufactured by Allegro MicroSystems, designed for fully integrated control and power stage applications in stepper motor systems. This 16-DIP through-hole component operates within a 4.75V to 5.5V supply voltage range and delivers 650mA output current across four half-bridge configurations.

The A3966SA is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain reliability, and support legacy system maintenance where original components are no longer readily available or have reached end-of-life status.

Substiute Parts

A3966SA

Allegro MicroSystemsIn Stock: 1912A3966SA Datasheet

Current PartRFQ

LV8734VL-TLM-H

onsemiIn Stock: 1095LV8734VL-TLM-H Datasheet

MFR RecommendedRFQ

TB6562AFG,8,EL

Toshiba Semiconductor and StorageIn Stock: 10413TB6562AFG,8,EL Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the A3966SA is determined by the following critical parameters:

Functional Requirements:

• Motor driver type: Bipolar stepper motor driver
• Output configuration: Four half-bridge stages
• Interface type: Parallel control interface
• Fully integrated control and power stage

Electrical Compatibility Criteria:

• Output current capability: Minimum 650mA (substitute parts must meet or exceed this requirement)
• Supply voltage range: Must accommodate the original 4.75V to 5.5V operating window or provide compatible overlap
• Load voltage range: Must support 4.75V to 30V operation
• Operating temperature range: Must cover or exceed -20°C to 150°C

Physical and Manufacturing Considerations:

• Mounting type: Original is through-hole; substitutes may be surface-mount with appropriate board redesign
• Package compatibility: Direct pin-compatible substitutes preferred; alternative packages require circuit board modification

The two substitute parts listed below meet the functional and electrical requirements for bipolar stepper motor driver applications, though each introduces different trade-offs in supply voltage range, output current, package type, and thermal operating range.

Parameter Comparison

Engineering Selection Recommendations

LV8734VL-TLM-H (onsemi): This substitute provides the broadest supply voltage compatibility, accepting 0V to 5.5V input, which fully encompasses the original A3966SA operating range. Output current is doubled to 1.5A, providing design margin for motor applications. The part is RoHS3 compliant and carries active product status, ensuring long-term availability and supply chain support. The 44-LSSOP surface-mount package requires PCB redesign but offers superior thermal characteristics. Operating temperature range is -40°C to 85°C, which covers the original lower bound but does not extend to the original 150°C maximum junction temperature.

TB6562AFG,8,EL (Toshiba Semiconductor and Storage): This substitute operates within a 10V to 34V supply voltage range, which does not overlap with the original 4.75V to 5.5V specification. This part is suitable only for applications where the system supply voltage can be redesigned to operate at 10V or higher. Output current is 1.5A, matching the onsemi alternative. The part is RoHS3 compliant with active product status. The 30-BSOP surface-mount package requires PCB redesign. Operating temperature range is -20°C to 85°C, matching the original lower bound but not extending to 150°C.

Selection Basis:

• For designs requiring minimal circuit modification and voltage compatibility with the original specification: LV8734VL-TLM-H is the preferred substitute.
• For applications where supply voltage can be increased to 10V or higher: TB6562AFG,8,EL is a viable alternative.
• Both substitutes require PCB redesign due to surface-mount packaging versus the original through-hole format.
• Both substitutes are RoHS3 compliant, supporting modern regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can the LV8734VL-TLM-H directly replace the A3966SA without circuit modification?

A: The LV8734VL-TLM-H provides functional and electrical compatibility for bipolar stepper motor driver applications. However, direct replacement is not possible due to package differences: the original A3966SA uses 16-DIP through-hole mounting, while the LV8734VL-TLM-H uses 44-LSSOP surface-mount packaging. PCB redesign is required. Pin mapping and control signal routing must be verified against both datasheets before implementation.

Q: What is the key difference between the two substitute parts?

A: The primary difference is supply voltage range. The LV8734VL-TLM-H accepts 0V to 5.5V, fully compatible with the original 4.75V to 5.5V specification. The TB6562AFG,8,EL requires 10V to 34V supply voltage, necessitating system redesign if the original operates at 5V. Both provide 1.5A output current, exceeding the original 650mA specification.

Q: Why does the A3966SA have a higher maximum operating temperature than the substitutes?

A: The A3966SA specifies 150°C maximum junction temperature (TJ), while substitutes specify 85°C maximum ambient temperature (TA). These are different measurement points. Junction temperature is measured at the die; ambient temperature is measured at the device exterior. Direct thermal comparison requires detailed thermal modeling and is not determinable from specification sheets alone.

Q: Are both substitute parts RoHS compliant?

A: Yes. Both the LV8734VL-TLM-H and TB6562AFG,8,EL are RoHS3 compliant. The original A3966SA is RoHS non-compliant. If RoHS compliance is a design requirement, either substitute part satisfies this criterion.

Q: Can I use the TB6562AFG,8,EL in a 5V system?

A: No. The TB6562AFG,8,EL requires a minimum supply voltage of 10V. It cannot operate at the original 4.75V to 5.5V specification without system redesign to increase supply voltage to at least 10V.

Q: What mounting considerations apply when switching from the A3966SA to a substitute?

A: The A3966SA is through-hole mounted on a DIP socket or directly soldered to the PCB. Both substitutes are surface-mount devices requiring reflow soldering and PCB layout redesign. Through-hole to surface-mount conversion involves changes to footprint, trace routing, and thermal management design.