A3982SLB-T - 35V, ±2A Bipolar Stepper Motor Driver | Allegro
N.º de pieza: A3982SLB-T ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $6.15 | $6,15 |
| 10 | $5.52 | $55,20 |
| 100 | $4.85 | $485,00 |
| 500 | $4.1 | $2.050,00 |
| 1.000 | $3.65 | $3.650,00 |
| 3.000 | $3.2 | $9.600,00 |
A3982SLB-T Descripción general
A stepper motor driver is an integrated power stage that converts low-level logic pulses into precisely commutated full-bridge currents through two motor windings. Within the broader power management hierarchy, this device sits inside the Motor Drivers sub-category of Power Management ICs. By integrating dual H-bridges, current-sense comparators, and a translator, the A3982SLB-T replaces what would otherwise be a discrete FET bridge plus op-amp sense circuit plus FPGA timing logic, shrinking BOM count and freeing board area.
Key features include a fixed off-time PWM current regulator, selectable Slow or Mixed decay modes, synchronous rectification for lower power dissipation, and internal crossover current protection. The logic inputs are 3.3 V and 5 V compatible, simplifying connection to common microcontrollers. Internal thermal shutdown and under-voltage lockout safeguard the DMOS outputs during fault conditions.
The A3982 uses a BCDMOS process that pairs bipolar precision analog blocks with DMOS output power stages, achieving low on-resistance around 0.5 ohm per leg at full scale and fast 35 V switching transitions. The fixed off-time current chopping regulator maintains ±5% torque accuracy by comparing sense-resistor voltage to an internal DAC-controlled reference.
Typical applications include textile and sewing machines, printers, scanners, small CNC routers, and automated teller machines. Industrial designers favor this driver for 24 V bus stepper rails up to 2 A per phase. When laying out the PCB, keep the high-current motor traces short and use a low-ESR supply bypass capacitor rated for the full motor stall current.
Alternativas directas para A3982SLB-T — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con A3982SLB-T (mismo factor de forma y huella) — difiere en Output Configuration, Package.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
A3982SLBTR-T
✅ Sustitución directa✓ En stock
$4.63 / unidad
Ver hoja de datos →A3982SLB
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
A3982SLB-T Valores máximos y características eléctricas
| Motor Type | Bipolar Stepper |
| Step Mode | Full-step, Half-step |
| Configuración de salida | Dual Full Bridge |
| Load Voltage (Vbb) | 8 V to 35 V |
| Output Drive Current | ±2 A per phase |
| Logic Supply Voltage (Vdd) | 3.0 V to 5.5 V |
| Current Control | Fixed off-time PWM with Slow / Mixed decay |
| Translator | Built-in (step-and-direction interface) |
| Rectificación síncrona | Yes |
| Apagado térmico | Yes |
| Under-Voltage Lockout | Yes |
| Temperatura de funcionamiento | -20 C to +85 C |
| Encapsulado | 24-SOIC (Wide, 300 mil, 7.50 mm) |
| Tipo de montaje | Surface Mount |
| Estado RoHS | Compliant |
Configuración de pines de A3982SLB-T
| Pin 1 | VBB — Motor supply voltage (8 V to 35 V) |
| Pin 2 | OUT1A — H-bridge output 1A to motor winding A |
| Pin 3 | SENSE1 — Current-sense resistor return for phase 1 |
| Pin 4 | OUT1B — H-bridge output 1B to motor winding A |
| Pin 5 | GND — Power ground |
| Pin 6 | OUT2A — H-bridge output 2A to motor winding B |
| Pin 7 | SENSE2 — Current-sense resistor return for phase 2 |
| Pin 8 | OUT2B — H-bridge output 2B to motor winding B |
| Pin 9 | NC — Not connected (per datasheet) |
| Pin 10 | NC — Not connected (per datasheet) |
| Pin 11 | NC — Not connected (per datasheet) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | VDD — Logic supply voltage (3.0 V to 5.5 V) |
| Pin 14 | STEP — Step input (rising edge advances one step) |
| Pin 15 | DIR — Direction logic input |
| Pin 16 | ENABLE — Enable logic input (active low) |
| Pin 17 | MS1 — Mode select (full / half step) |
| Pin 18 | DECAY — Decay mode select (Slow / Mixed) |
| Pin 19 | REF — Current-set reference input voltage |
| Pin 20 | ROSC — Off-time programming resistor |
| Pin 21 | GND — Logic ground |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Aplicaciones típicas
A3982SLB-T es adecuado para 6 aplicacións: Industrial 3D Printer and CNC Stepper Drive, Textile and Sewing Machine Motor Control, Label and Barcode Printer Carriage Drive, Document Scanner and Plotter Stepper Axes, ATM Cash-Dispenser Stepper Drive, Robotics and Pick-and-Place Automation.
Industrial 3D Printer and CNC Stepper Drive
The A3982SLB-T fits 3D-printer and small CNC applications because its 35 V and ±2 A per-phase output drives NEMA 17 and small NEMA 23 stepper motors directly from a 24 V industrial bus. The built-in translator accepts step-and-direction pulses from a Marlin, GRBL, or Klipper host MCU without an external indexer, reducing BOM and firmware complexity. The Mixed decay mode maintains accurate torque at step rates above 500 pps, which is the practical operating envelope for hobby-class motion-control rigs. Designers can rely on the 3.3 V / 5 V compatible logic interface to connect directly to Raspberry Pi, STM32, and ESP32 GPIO without level shifters. The fixed off-time current chopper gives ±5% torque repeatability per step, sufficient for filament extrusion and small-mill spindle positioning.
Recomendado
Textile and Sewing Machine Motor Control
The A3982SLB-T is well suited to textile machinery where multiple axes of stepper motors must be synchronized from a 24 V supply. Its ±2 A per-phase output handles the typical NEMA 17 sewing head and thread tensioner motors found in embroidery equipment. The SOIC-24 Wide footprint plus integrated translator allow compact driver boards to be placed near each motor, shortening the high-current trace loop and reducing EMI. Slow decay mode is preferable at low step rates to minimize audible noise from the chopper regulator. Built-in thermal shutdown protects the driver when the sewing head stalls due to thread jam. Allegro's decades-long presence in this segment confirms the part's reliability for 24/7 factory duty cycles.
Recomendado
Label and Barcode Printer Carriage Drive
Commercial label and barcode printers use the A3982SLB-T to drive the carriage stepper motor that advances print heads and feeds media. The part's ±2 A and 35 V output matches typical 24 V print-head carriage motors up to NEMA 17. Half-step mode gives sufficient resolution for label positioning, while the synchronous rectification feature keeps the part cool under continuous duty in warehouse printers. The logic supply accepts 3.3 V, allowing direct connection to modern printer controller ASICs without level shifting. The internal under-voltage lockout protects the print-head stepper from undefined motion during brown-out conditions.
Recomendado
Document Scanner and Plotter Stepper Axes
The A3982SLB-T drives the X/Y carriage stepper motors inside flatbed scanners, film scanners, and pen plotters. The integrated translator eliminates the external FPGA indexer that would otherwise be required for synchronized dual-axis motion. With ±2 A available per phase, the part drives NEMA 14 and NEMA 17 carriage motors typically found in A3-size plotters. The Slow decay mode provides low audible noise during office-environment operation. Mixed decay can be enabled when the carriage accelerates at the start of a scan line, suppressing current ripple that would otherwise appear as horizontal banding in the captured image.
Recomendado
ATM Cash-Dispenser Stepper Drive
Banking ATMs deploy the A3982SLB-T to drive bill feeder and shutter stepper motors that must operate reliably 24/7 in unattended environments. The ±2 A drive handles the bill-thickness sensor and shutter NEMA 17 motors typical in NCR and Diebold dispensers. Mixed decay mode keeps current ripple low under frequent start-stop cycles, reducing mechanical wear on the cash transport mechanism. The integrated thermal shutdown and under-voltage lockout meet the stringent fault-tolerance requirements of financial self-service equipment. Allegro's long product-life-cycle support program makes the A3982SLB-T a low-risk choice for ATM OEMs planning 10-year field support.
Recomendado
Robotics and Pick-and-Place Automation
Small-payload pick-and-place machines and desktop robotics arms use the A3982SLB-T to drive the shoulder, elbow, and gripper stepper motors. Its 35 V / ±2 A envelope supports 24 V supply rails common in factory automation, with enough current margin for NEMA 17 joint motors. The built-in step-and-direction interface connects directly to industrial PLC motion modules or Arduino shields, simplifying firmware development. Mixed decay mode gives accurate current regulation during the rapid direction changes typical in pick-and-place trajectories. Internal crossover-current protection prevents shoot-through when the host MCU toggles direction at high speed.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para A3982SLB-T — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | A3982SLBTR-T | A3982SLB |
|---|---|---|---|
| Brand | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems |
| Package | 24-SOIC (Wide, 300 mil) | 24-SOIC (Wide, 300 mil) - same | 24-SOIC (Wide, 300 mil) - same |
| Output Current per Phase | ±2 A | ±2 A | ±2 A |
| Motor Supply Voltage | 8 V to 35 V | 8 V to 35 V | 8 V to 35 V |
| Step Resolution | Full, Half | Full, Half | Full, Half |
| Built-in Translator | Yes | Yes | Yes |
| Decay Modes | Slow, Mixed | Slow, Mixed | Slow, Mixed |
| Packaging Format | Tube | Tape and Reel | Tube |
| Logic Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Approx. Unit Price (qty 1, as of 2026-10-06) | $6.15 | $6.15 | $6.15 |
Diferenciadores clave
- Integrated step-and-direction translator (frente a A3982SLBTR-T)
- Commercial-grade pricing on the SOIC-24 Wide footprint (frente a A3982SLB)
- Drop-in alternative footprint versus A3977SLPTR-T (frente a A3977SLPTR-T (TSSOP-28))
Notas de diseño
Estimated: at VIN = 24 V, full-scale ±2 A output, and 50% step rate duty cycle, the A3982SLB-T dissipates roughly 5-6 W into the SOIC-24 Wide package. With a typical θJA near 50 C/W on a 4-layer JEDEC board, junction temperature rises 250-300 C above ambient without copper spreading or forced-air cooling. Designers must pour at least 1 square inch of top-layer copper under the exposed pad region and consider a small clip-on heatsink if continuous 2 A operation is required.
Place the 100 uF Vbb bulk capacitor within 5 mm of the Vbb pin (pin 1) and use a star-ground connection tying GND (pin 5) directly back to the bulk capacitor negative terminal. Route the high-current OUT1A, OUT1B, OUT2A, OUT2B traces as parallel pairs with at least 2 oz copper weight to minimize inductance. Keep the SENSE1/SENSE2 Kelvin traces short and place a low-inductance ground plane under the sense resistors to avoid PWM noise injection into the current-control loop.
Do not omit the ROSC off-time resistor on pin 20, otherwise the current chopper will default to its minimum off-time and may overheat the H-bridges. The REF voltage on pin 19 sets peak phase current according to ITRIP = VREF / (8 × Rsense); a typical 0.5 ohm sense resistor with VREF = 3.3 V yields approximately 0.825 A, not 2 A. Always double-check the sense-resistor value and REF divider ratio before assuming full-scale current.
The STEP input on pin 14 should be driven by a clean logic signal with rise/fall times below 100 ns to avoid double-stepping artifacts. Add a 1 kohm series resistor plus a 100 pF capacitor at the STEP pin if the host MCU is more than 50 mm away to damp transmission-line ringing. Place a 0.1 uF decoupling capacitor on VDD (pin 13) within 3 mm to suppress logic-supply glitches when the H-bridges switch.
Información de cumplimiento
RoHS compliant and lead-free per Allegro product page. Not AEC-Q100 qualified; commercial/industrial grade. Halogen-free status not explicitly stated in the retrieved data.