Part A
A3966SLBTR-T
Allegro MicroSystems
- Lifecycle
- Active
- Stock
- 7796 PCS
- Package
- SOIC-16
- Series
- PMIC - Motor Drivers, Controllers
Replacement verdict
Compatible functional replacement candidate
The A3966SLBTR-T and A3966SLB-T are functionally equivalent dual full-bridge PWM motor drivers from Allegro MicroSystems, sharing identical die, electrical characteristics, and SOIC-16 package construction. The only distinction is the packing format: the A3966SLBTR-T is supplied on tape and reel for automated assembly, while the A3966SLB-T is supplied in tube form. Either device can serve as a direct substitute for the other provided the board assembly process accommodates the corresponding packaging.
Function and Output Type
High match
Package Type
High match
Electrical Ratings
High match
Packing Format
Validation required
Parts at a glance
Part B
A3966SLB-T
Allegro MicroSystems
- Lifecycle
- Active
- Stock
- 3731 PCS
- Package
- SOIC-16
- Series
- PMIC - Motor Drivers, Controllers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | A3966SLBTR-T | A3966SLB-T | Why it matters |
|---|---|---|---|
| Manufacturer | Allegro MicroSystems | Allegro MicroSystems | Identical manufacturer ensures the same design, process, and quality standards for both parts. |
| Product Category | Motor Driver ICs - Stepper Motor Controller | Motor Driver ICs - Stepper Motor Controller | Same functional category confirms both devices serve the same application role. |
| Output Configuration | Dual Full-Bridge (H-Bridge) | Dual Full-Bridge (H-Bridge) | Matching output topology ensures equivalent drive capability for bipolar stepper motors. |
| Supply Voltage Range | 4.75 V to 5.25 V (logic), 4.5 V to 36 V (motor) | 4.75 V to 5.25 V (logic), 4.5 V to 36 V (motor) | Identical voltage ranges allow direct substitution without redesigning the power supply. |
| Output Current per Channel | 750 mA | 750 mA | Same current rating ensures equivalent torque and load-driving capability. |
| Package / Case | 16-PowerSOIC (0.295", 7.50mm Width) | 16-PowerSOIC (0.295", 7.50mm Width) | Identical package footprint allows drop-in replacement on the same PCB layout. |
| Mounting Type | Surface Mount | Surface Mount | Both are surface mount, but the tape-and-reel versus tube packaging difference affects assembly line handling. |
| Packaging | Tape & Reel (TR) | Tube | Packaging determines how the parts are fed into automated pick-and-place equipment versus manual handling. |
| Operating Temperature Range | -20°C to +85°C | -20°C to +85°C | Same thermal range ensures both parts perform reliably in identical environmental conditions. |
| RoHS Status | RoHS Compliant | RoHS Compliant | Both meet the same environmental regulations, simplifying compliance for the final product. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | A3966SLBTR-T | A3966SLB-T |
|---|---|---|
| Part Status | Active | Obsolete |
| Motor Type - Stepper | Bipolar | Bipolar |
| Function | Driver - Fully Integrated, Control and Power Stage | Driver - Fully Integrated, Control and Power Stage |
| Output Configuration | Half Bridge (4) | Half Bridge (4) |
| Interface | Parallel | Parallel |
| Technology | Bipolar | Bipolar |
| Applications | General Purpose | General Purpose |
| Current - Output | 650mA | 650mA |
| Voltage - Supply | 4.75V ~ 5.5V | 4.75V ~ 5.5V |
| Voltage - Load | 4.75V ~ 30V | 4.75V ~ 30V |
| Operating Temperature | -20°C ~ 150°C (TJ) | -20°C ~ 150°C (TJ) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What is the difference between the A3966SLBTR-T and the A3966SLB-T?
The A3966SLBTR-T and A3966SLB-T are the same Allegro MicroSystems A3966 dual full-bridge motor driver die in the same 16-lead SOIC-wide (LB) package. The difference is the ordering and packing suffix: the A3966SLBTR-T is supplied in tape and reel, while the A3966SLB-T is supplied in tube. Both are lead (Pb) free and RoHS compliant, and both are specified over the industrial temperature range of -20°C to +85°C.
Are the A3966SLBTR-T and A3966SLB-T electrically and functionally identical?
Yes. Both part numbers refer to the same A3966 device, which is a dual full-bridge driver with internal fixed off-time PWM current control, capable of continuous output currents up to ±650 mA and operating voltages from 4.75 V to 5.5 V for the logic supply and up to 30 V for the load supply. The electrical specifications, pinout, and functional behavior are identical; only the shipping format differs.
Can the A3966SLBTR-T and A3966SLB-T be used interchangeably in a design?
Yes, they are electrically and mechanically interchangeable because they share the same die, package, and pinout. The only practical difference is the packaging format for automated assembly: the A3966SLBTR-T is tape and reel for pick-and-place equipment, while the A3966SLB-T is tube for manual or low-volume handling. Design validation is not required when switching between them.
What is the package and pinout of the A3966SLBTR-T and A3966SLB-T?
Both devices use the 16-lead SOIC-wide (LB) package, which is a surface-mount plastic package with a 7.50 mm body width and 1.27 mm lead pitch. The pinout includes logic supply, load supply, ground, two full-bridge outputs, and control inputs for direction, brake, and PWM current control. The package is identical for both ordering suffixes.
What are the recommended operating conditions for the A3966SLBTR-T and A3966SLB-T?
Both devices are specified for a logic supply voltage (VCC) of 4.75 V to 5.5 V, a load supply voltage (VS) up to 30 V, and an operating ambient temperature range of -20°C to +85°C. Continuous output current per bridge is ±650 mA, with peak currents up to ±1.1 A. These ratings are identical for both the tape-and-reel and tube versions.
Do the A3966SLBTR-T and A3966SLB-T have the same thermal characteristics?
Yes. Because both part numbers use the same 16-lead SOIC-wide package and the same silicon die, the thermal resistance (junction-to-ambient, RθJA) and power dissipation limits are identical. The thermal performance depends only on the package and PCB layout, not on the shipping format.
Which part number should be selected for automated production?
For automated pick-and-place assembly, the A3966SLBTR-T is the appropriate choice because it is supplied in tape and reel, which is compatible with high-speed SMT equipment. The A3966SLB-T in tube is better suited for manual assembly, prototyping, or low-volume production. Both provide the same device performance.
Are the A3966SLBTR-T and A3966SLB-T RoHS compliant and lead-free?
Yes. Both the A3966SLBTR-T and A3966SLB-T are lead (Pb) free and RoHS compliant, as indicated by the "-T" suffix in the ordering code, which denotes a lead-free finish. The tape-and-reel and tube packaging options do not affect the material compliance of the device itself.