A3941KLPTR-T - 50V Full-Bridge MOSFET Driver | Allegro | Automotive
N.º da peça: A3941KLPTR-T ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $3.5 | $3,50 |
| 10 | $3.15 | $31,50 |
| 100 | $2.75 | $275,00 |
| 500 | $2.4 | $1.200,00 |
| 1.000 | $2.1 | $2.100,00 |
| 2.500 | $1.85 | $4.625,00 |
A3941KLPTR-T Visão geral
A full-bridge MOSFET driver is a half-H or full-H control IC that translates low-current logic-level direction and PWM commands into high-current gate signals capable of slewing large power MOSFET gates at the high dV/dt rates typical of 12 V and 24 V automotive buses. Full-bridge drivers sit within the broader hierarchy of motor control ICs -> brushed DC drivers -> gate drivers -> power management semiconductors. By moving the power-MOSFET selection to external discretes, full-bridge controllers let designers optimize RDS(on), current rating, and thermal dissipation for the specific motor, while the IC handles timing, dead-time, charge-pump generation, and fault protection.
Key features of the A3941KLPTR-T include a wide 5.5 V to 50 V supply range, integrated charge pump that maintains full >10 V gate drive down to 7 V VBAT, 100% duty-cycle bootstrap-capable high-side drive, programmable dead time, internal 5 V regulator for logic supply, diagnostics output, and protection against short-to-ground, short-to-battery, and over-temperature. Synchronous rectification switching minimizes body-diode conduction losses during PWM-freewheeling. The TSSOP-EP package exposes the die for a low theta_JA conduction path to PCB copper.
Typical applications include automotive HVAC blowers, fuel pumps, water pumps, oil pumps, engine cooling fans, and electric power steering auxiliary motors. The high current gate drive also suits industrial brush DC drives, AGV traction motors up to several hundred watts, and 24 V solenoid drivers. Diagnostic feedback enables ISO 26262 functional-safety system designs in body and chassis ECUs.
When designing with the A3941KLPTR-T, ensure adequate PCB copper area beneath the exposed pad to keep junction temperature within safe limits. Place bootstrap capacitors as close as possible to their respective BST pins and use 100 nF ceramic bypass on VREG and V5. The PWML/PWMH logic inputs allow independent control of each half-bridge, enabling forward, reverse, brake, and coast modes with a single direction bit.
Alternativas drop-in para A3941KLPTR-T — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
A3941KLPTR
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
A3941KLPT
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
A3941SLPTR-T
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
A3940KLPTR-T
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
A3941KLPTR-T Classificações máximas e características elétricas
| Função | Full-bridge N-channel MOSFET driver |
| Supply Voltage (VBAT) | 5.5 V to 50 V |
| Minimum VBAT for Full Gate Drive | 7 V (with charge pump, VGS > 10 V) |
| Gate Drive Voltage | >10 V (typ.) |
| Número de saídas | 4 (high-side GHA/LA, low-side GLA/LB) |
| Configuração de saída | Full bridge (H-bridge), high-side or low-side PWM |
| Topologia | Synchronous rectification with charge pump and bootstrap |
| Propagation Delay | 90 ns (typ.) |
| Dead Time | Programmable (RDEAD resistor) |
| Temperatura de operação | -40 C to +150 C (junction) |
| Encapsulamento | 28-pin TSSOP-EP (LP package) |
| Tipo de montagem | Surface Mount |
| Status RoHS | Compliant |
| Automotive Qualification | AEC-Q100 automotive grade |
| Fault Protection | Short-to-ground, short-to-battery, over-temperature, VDS monitoring |
| Internal 5 V Regulator | Yes (VREG/V5 outputs) |
Configuração de pinos do A3941KLPTR-T
| Pino 1 | GLA — Low-side gate A (output to external N-FET) |
| Pino 2 | GHA — High-side gate A (output to external N-FET, bootstrap referenced) |
| Pino 3 | SA — Source/phase A (low-side FET source / motor phase A) |
| Pino 4 | CA — Phase A drain sense / high-side FET drain sense |
| Pino 5 | BOOTA — Bootstrap capacitor for high-side gate A |
| Pino 6 | VDRAIN — Drain voltage monitor input (high-side drain sense) |
| Pino 7 | VDSTH — VDS threshold programming input |
| Pino 8 | RDEAD — Dead-time programming resistor |
| Pino 9 | FF2 — Fault flag 2 (latched fault output) |
| Pino 10 | SR — Slew-rate control / synchronous rectification enable |
| Pino 11 | CP1 — Charge pump flying capacitor node 1 |
| Pino 12 | CP2 — Charge pump flying capacitor node 2 |
| Pino 13 | VREG — Internal regulator output (low-current logic supply) |
| Pino 14 | V5 — 5 V internal regulator decoupling / output |
| Pino 15 | VBAT — Battery supply input (5.5 V to 50 V) |
| Pino 16 | PWML — PWM logic input, low-side |
| Pino 17 | PWMH — PWM logic input, high-side |
| Pino 18 | BOOTB — Bootstrap capacitor for high-side gate B |
| Pino 19 | CB — Phase B drain sense / high-side FET drain sense |
| Pino 20 | SB — Source/phase B (low-side FET source / motor phase B) |
| Pino 21 | GHB — High-side gate B (output to external N-FET, bootstrap referenced) |
| Pino 22 | GLB — Low-side gate B (output to external N-FET) |
| Pino 23 | LSS — Low-side source / ground return for gate drivers |
| Pino 24 | NC — Not connected (per datasheet) |
| Pino 25 | NC — Not connected (per datasheet) |
| Pino 26 | NC — Not connected (per datasheet) |
| Pino 27 | NC — Not connected (per datasheet) |
| Pino 28 | NC — Not connected (per datasheet) |
| Pino EP | EP — Exposed thermal pad - solder to PCB ground plane for thermal dissipation |
Aplicações típicas
A3941KLPTR-T é adequado para 6 aplicaçãos: Automotive HVAC Blower Motor, Automotive Fuel Pump Driver, Engine Cooling Fan, Industrial 24 V Brushed DC Motor Drive, AGV Traction Motor Controller, Solenoid and Valve Driver.
Automotive HVAC Blower Motor
The A3941KLPTR-T is well matched to driving the brush DC blower motor in an automotive HVAC module. Its 5.5 V to 50 V VBAT range tolerates 12 V nominal bus transients including load-dump spikes to 35 V and cold-crank dips to 6 V; the integrated charge pump keeps the external N-FET VGS above 10 V even at 7 V VBAT, so RDS(on) stays low and conduction loss stays bounded across the full automotive envelope. The 90 ns propagation delay and programmable dead time produce clean PWM switching with low EMI, important for the cabin EMC environment. Diagnostic outputs (short-to-ground, short-to-battery, over-temperature) feed the HVAC ECU for ISO 26262 functional safety. Place the A3941KLPTR-T adjacent to the blower FETs with a 4-layer FR4 PCB and at least 1 sq-inch of copper on the exposed pad to dissipate gate-charge and switching losses.
Recomendado
Automotive Fuel Pump Driver
Brush DC fuel pumps demand a high-current full-bridge driver that can PWM regulate pressure while surviving harsh under-hood thermal and electrical environments. The A3941KLPTR-T supports continuous high-side duty cycles through its bootstrap-and-charge-pump architecture, giving the fuel-pump controller smooth average-current regulation from 0 to 100% PWM. The 50 V VBAT rating tolerates 24 V truck architectures and jump-start events; the -40 C to +150 C junction range handles under-hood ambient. Synchronous rectification reduces body-diode losses during freewheeling, improving efficiency and reducing pump noise. The diagnostic pins can be wired to the ECU to flag a stalled-rotor or shorted-winding condition. Use four TO-220 or DFN N-FETs sized for the pump's worst-case stall current, with the A3941KLPTR-T TSSOP-EP exposed pad on a copper area of at least 1 square inch.
Recomendado
Engine Cooling Fan
Engine cooling fans are large brush DC loads that must be PWM-controlled from the engine ECU across a wide speed range, often from idle creep to high-speed cooling. The A3941KLPTR-T's wide VBAT range and 100% duty-cycle high-side drive make it suitable for engine-fan applications at 12 V or 24 V. The integrated charge pump keeps VGS above 10 V even during cold-crank at 7 V VBAT, so the fan does not stall due to insufficient gate drive. The 90 ns propagation delay allows PWM frequencies up to the audio range without audibly exciting the motor windings, an important comfort consideration in cabin-mounted fans. The short-to-ground and short-to-battery diagnostics protect the FETs when the harness is miswired or chafed, common failure modes in under-hood wiring. Mount the TSSOP-EP pad to a copper pour equal to at least 1 sq-inch for thermal performance.
Recomendado
Industrial 24 V Brushed DC Motor Drive
Industrial automation frequently uses 24 V brushed DC motors for conveyor rollers, gate actuators, and AGV traction wheels. The A3941KLPTR-T's 5.5 V to 50 V VBAT and >10 V gate drive at 7 V input is well matched to the 24 V industrial bus. Its programmable dead time allows the designer to tune for the chosen N-FET family, minimizing shoot-through and switching loss. Synchronous rectification improves efficiency enough to shrink heatsinking in enclosed IP54 cabinets. The TSSOP-EP package allows compact PCB layouts when co-located with the power FETs. Diagnostic feedback integrates cleanly with industrial PLCs and CANopen nodes. Use the A3941KLPTR-T's PWML/PWMH inputs for independent half-bridge control to implement forward, reverse, brake, and coast with a single direction bit from the controller.
Recomendado
AGV Traction Motor Controller
Automated guided vehicles use low-voltage brushed DC traction motors in the 100 W to 500 W range, driven from 24 V or 48 V battery packs. The A3941KLPTR-T's 50 V VBAT rating covers 24 V and 36 V packs with margin, and its integrated charge pump keeps the N-FETs fully enhanced even as the battery sags under load. The TSSOP-EP exposed pad gives a low-thermal-resistance path to the PCB, allowing continuous traction current in a compact footprint. Synchronous rectification improves run time by reducing I*RDS(on) and body-diode losses, directly extending battery life. The A3941KLPTR-T's fault outputs feed the AGV safety PLC, which can cut PWM and engage the mechanical brake on a stall or over-current event. Co-locate the A3941KLPTR-T with the FETs and a current-sense shunt, returning the diagnostic output to the controller.
Recomendado
Solenoid and Valve Driver
The A3941KLPTR-T's half-bridge mode can be used independently to drive 24 V solenoids, hydraulic valves, and latching relays in industrial and automotive systems. Each of the four gate outputs can be commanded separately via PWML and PWMH, allowing the A3941KLPTR-T to replace two conventional high-side drivers. The integrated 5 V regulator (VREG/V5) can supply logic-level microcontrollers or CAN transceivers, eliminating an external LDO and saving board space. The short-to-ground and over-temperature diagnostics provide immediate fault feedback, and the wide VBAT tolerance handles 24 V industrial buses with large inductive kickback transients. Bootstrap capacitors on the high-side drivers ensure 100% duty-cycle operation needed for sustained solenoid hold.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para A3941KLPTR-T — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | A3941KLPTR | A3941KLPT | A3941SLPTR-T | A3940KLPTR-T |
|---|---|---|---|---|---|
| Package | 28-pin TSSOP-EP (LP) | 28-pin TSSOP-EP (LP) - same | 28-pin TSSOP-EP (LP) - same | 28-pin TSSOP-EP (LP) - same | 28-pin TSSOP-EP (LP) - same |
| Brand | Allegro MicroSystems | Allegro MicroSystems - same | Allegro MicroSystems - same | Allegro MicroSystems - same | Allegro MicroSystems - same |
| Supply Voltage (VBAT) | 5.5 V to 50 V | 5.5 V to 50 V | 5.5 V to 50 V | 5.5 V to 50 V | 5.5 V to 50 V (predecessor) |
| Minimum VBAT for Full VGS | 7 V (VGS > 10 V) | 7 V | 7 V | 7 V | 8.5 V (typical) |
| Propagation Delay | 90 ns (typ.) | 90 ns | 90 ns | 90 ns | 200 ns (typ.) |
| Dead Time Control | Programmable via RDEAD | Programmable via RDEAD | Programmable via RDEAD | Programmable via RDEAD | Fixed internal dead time |
| Automotive Qualification | AEC-Q100 | AEC-Q100 | AEC-Q100 | AEC-Q100 | AEC-Q100 (legacy) |
| Packaging Media | Tape & Reel (T suffix) | Tray / cut tape (no T suffix) | Tube (no R suffix) | Tape & Reel (T suffix) | Tape & Reel (T suffix) |
| Approx. Unit Price (1k qty) | $2.10 (as of 2026-10-06) | $2.10 (same die, packaging varies) | $2.20 (tube, slightly higher) | $2.30 (option variant) | $1.90 (legacy, NRND risk) |
Principais diferenciais
- Integrated charge pump maintains >10 V VGS down to 7 V VBAT (vs A3940KLPTR-T (predecessor))
- Programmable dead time via RDEAD pin (vs A3940KLPTR-T (predecessor))
- Comprehensive fault diagnostics (short-to-battery, short-to-ground, VDS, OT) (vs A3940KLPTR-T (predecessor))
- Synchronous rectification with SR control pin (vs A3940KLPTR-T (predecessor))
Notas de projeto
The 28-pin TSSOP-EP package dissipates switching and gate-drive losses through the exposed thermal pad on the underside of the IC. Without a continuous PCB copper pour beneath the pad, theta_JA rises sharply and the device will enter thermal shutdown under sustained load. Provide at least 1 square inch of 2 oz copper on the top or bottom layer connected to the pad, with multiple thermal vias to the opposite copper plane for higher current designs. Estimated: at 1 A average motor current with 24 V bus and 50% PWM, conduction loss in the external FETs dominates; the A3941KLPTR-T itself typically dissipates < 0.3 W, but at higher bus voltages the gate-charge losses scale linearly with switching frequency.
Place the bootstrap capacitors (CB) as close as physically possible to the BOOTA/BOOTB pins and their respective phase pins, using 100 nF X7R ceramic with the shortest possible trace length. Place the charge-pump flying capacitor between CP1 and CP2 with equally short traces. The VREG and V5 pins each require a 1 uF to 10 uF decoupling capacitor placed within 2 mm of the pin. Keep the high-di/dt gate-drive traces (GLA/GHA/GLB/GHB) away from analog feedback traces to prevent capacitive coupling and ground-bounce-induced logic errors.
Three pitfalls are common in first-time A3941 designs. First, omitting the RDEAD resistor forces the part into its default dead time, which may not match the chosen external FET family and will cause shoot-through at high duty cycle. Second, neglecting to populate the bootstrap capacitor on BOOTA or BOOTB causes the high-side FET to lose drive above ~95% duty cycle, which manifests as a sudden loss of torque at high PWM. Third, ignoring the exposed-pad solder connection leads to thermal shutdown within seconds of full-load operation - the pad must be soldered, not just present on the footprint.
The A3941KLPTR-T's charge pump draws additional quiescent current proportional to the PWM rate of the high-side FETs. At 25 kHz PWM with 50% duty cycle the additional VBAT current is on the order of 1-2 mA, negligible compared to motor current. However, very high PWM frequencies (>100 kHz) push the charge-pump current above 10 mA and should be accounted for in the quiescent budget. The internal 5 V regulator (VREG/V5) can supply up to approximately 50 mA for external logic - sufficient for a small MCU or CAN transceiver, but do not use it as a motor or solenoid power rail.
The PWML and PWMH inputs are standard 3.3 V / 5 V logic-level compatible, but the high-current gate-drive outputs (GLA/GHA/GLB/GHB) switch at dV/dt rates exceeding 1 V/ns. If the PWML/PWMH traces run parallel to the gate-drive outputs on the PCB, capacitive coupling can cause double-pulsing or timing jitter. Keep logic-level traces on an inner PCB layer with a continuous ground plane above or below, and route the gate-drive outputs on the outer layer with minimum trace length to the FET gates. Gate-series resistors of 10-47 ohm damp the LC tank formed by the gate-trace inductance and the FET gate capacitance.
Informações de conformidade
AEC-Q100 qualified per Allegro automotive-grade portfolio. RoHS and lead-free per Allegro product page. Halogen-free per Allegro MSL report.
