LM61440-Q1 - 36V, 4A Automotive Low-Noise Buck | Texas Instruments
N.º de pieza: LM61440Q-Q1 ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $4.55 | $4,55 |
| 10 | $4.1 | $41,00 |
| 100 | $3.55 | $355,00 |
| 500 | $3.1 | $1.550,00 |
| 1.000 | $2.78 | $2.780,00 |
LM61440Q-Q1 Descripción general
A synchronous buck converter (also called a step-down switching regulator) is a type of DC-DC converter within the power management IC hierarchy that uses two internal switches plus an inductor to efficiently convert a higher input voltage to a regulated lower output voltage. Compared to linear regulators, synchronous buck converters achieve efficiency typically above 90%, making them the default choice for automotive and industrial point-of-load power rails.
Key features include low EMI optimization for CISPR-class automotive requirements, a pin-selectable light-load mode trading efficiency versus ripple, adjustable switching frequency, and functional-safety-capable documentation to support ISO 26262 system designs. The HotRod package eliminates bond wires, reducing parasitic inductance and switch-node overshoot, which directly lowers radiated emissions.
Architecturally, the LM61440-Q1 uses a current-mode control topology with integrated FETs, achieving fast transient response and simplified external component selection. The 42 V transient tolerance protects against automotive load-dump and cold-crank conditions without expensive front-end suppression circuitry.
Typical applications include ADAS domain controllers, infotainment power trees, automotive body electronics, gateway modules, and industrial 24 V bus point-of-load conversion. Its wide 3 V to 36 V range covers 12 V and 24 V battery systems directly.
Design tip: keep the input capacitor loop as tight as possible to the VIN and PGND pins to fully exploit the HotRod parallel input path and minimize EMI; use spread-spectrum or adjustable frequency settings to avoid sensitive radio bands. Pin-compatible family members (LM61460, 6 A) allow current-scaling without PCB redesign.
Alternativas directas para LM61440Q-Q1 — 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 LM61440Q-Q1 (mismo factor de forma y huella) — difiere en Package, Input Voltage Range, Maximum Output Current, Dropout Behavior.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LM61440
✅ Sustitución directa✓ En stock
$2.1 / unidad
Ver hoja de datos →LM61460
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LM61460-Q1
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LM61440Q-Q1 Valores máximos y características eléctricas
| Topología | Synchronous Step-Down (Buck) |
| Rango de tensión de entrada | 3 V to 36 V |
| Input Transient Tolerance | 42 V |
| Corriente de salida máxima | 4 A |
| Número de salidas | 1 |
| Tipo de salida | Adjustable |
| Integrated MOSFETs | Yes (high-side and low-side) |
| Light Load Mode | Pin Selectable |
| EMI Performance | Low EMI, optimized for automotive |
| Functional Safety | Functional-Safety-Capable documentation available |
| Encapsulado | 14-Pin PowerVFQFN (VQFN-HR, HotRod, RJR) |
| Tipo de montaje | Surface Mount |
| Qualification | AEC-Q100 (automotive) |
Configuración de pines de LM61440Q-Q1
| Pin 1 | PVIN — Power input voltage, parallel input path |
| Pin 2 | PVIN/SW — Power input / switch node path |
| Pin 3 | SW — Switch node - connect to inductor |
| Pin 4 | BOOT — Bootstrap for high-side gate driver |
| Pin 5 | EN — Enable pin |
| Pin 6 | RT/SYNC — Frequency set / synchronization |
| Pin 7 | FB — Feedback input for output regulation |
| Pin 8 | AGND — Analog ground |
| Pin 9 | PGND — Power ground |
| Pin 10 | VCC — Internal LDO output / bias |
| Pin 11 | SS/TR — Soft-start / tracking |
| Pin 12 | MODE — Light-load mode selection |
| Pin 13 | PWRGD — Power good indicator (open drain) |
| Pin 14 | PGND/PAD — Power ground / thermal pad |
Aplicaciones típicas
LM61440Q-Q1 es adecuado para 6 aplicacións: ADAS Domain Controller Power, Automotive Infotainment, Automotive Gateway and Body Electronics, Industrial 24 V Bus Point-of-Load, Automotive Lighting and LED Drivers, Test and Measurement Instruments.
ADAS Domain Controller Power
The LM61440-Q1 fits ADAS domain controllers where sensor processors need clean, efficient mid-current rails from a 12 V automotive battery. Its 3 V to 36 V input with 42 V transient tolerance survives load-dump without front-end clampers, and AEC-Q100 qualification plus functional-safety documentation supports ISO 26262 system arguments. Placed as a first-stage 5 V or 3.3 V rail feeding downstream point-of-load regulators, its low-EMI HotRod package with parallel input path minimizes switch-node ringing that could interfere with radar and camera signal chains.
Recomendado
Automotive Infotainment
Infotainment head units and displays draw several amps at 5 V from a noisy 12 V battery rail shared with RF tuners and audio amplifiers. The LM61440-Q1's low-EMI switching and pin-selectable light-load mode keep conducted/radiated emissions within CISPR-class limits while maintaining efficiency at standby loads. The 4 A capacity directly powers display backplane or audio power stages, and the 36 V input covers jump-start and load-dump transients that would damage commercial-grade converters.
Recomendado
Automotive Gateway and Body Electronics
Gateway modules and body control units run continuously, so light-load efficiency matters. The LM61440-Q1's pin-selectable light-load mode keeps quiescent losses low during sleep states while providing 4 A bursts for CAN/LIN transceiver banks and microcontroller rails. Its 42 V transient tolerance eases input surge protection against ISO pulse events in harsh body-electronics environments. The AEC-Q100 qualification and functional-safety-capable documentation align with typical gateway reliability targets.
Recomendado
Industrial 24 V Bus Point-of-Load
Industrial PLC and factory automation systems distribute a 24 V bus that must be stepped down to 5 V or 3.3 V for I/O and sensors. The LM61440-Q1's 36 V maximum input covers 24 V rails plus surge margin, while its 4 A output feeds multiple I/O cards. The low-EMI design prevents interference with nearby analog measurement front ends, and adjustable switching frequency lets designers steer switching harmonics away from sensitive ADC bands used in industrial data acquisition.
Recomendado
Automotive Lighting and LED Drivers
Exterior and interior LED lighting modules in vehicles demand stable current rails from a battery subject to cold-crank dips (down near 3-4 V) and load-dump surges (up to 36-42 V). The LM61440-Q1 spans this entire envelope natively. Its 4 A capacity supports high-power LED strings via constant-voltage feeding of linear LED drivers, and the pin-selectable light-load mode enables PWM-dimming-friendly continuous conduction for low output ripple and uniform light output.
Recomendado
Test and Measurement Instruments
Bench instruments and data acquisition modules need efficient, low-noise intermediate rails from 12 V or 24 V wall adapters. The LM61440-Q1's 36 V input accepts both adapter standards, and its adjustable frequency plus spread of harmonics simplify compliance testing. The HotRod package reduces switch-node overshoot, improving radiated emissions margins in plastic-enclosed instruments without shielding, while 4 A covers DSP and FPGA I/O rail demands in compact designs.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LM61440Q-Q1 — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LM61440 | LM61460 | LMR61440-Q1 |
|---|---|---|---|---|
| Package | 14-Pin VQFN-HR (RJR, HotRod) | 14-Pin VQFN-HR (RJR) - same | 14-Pin VQFN-HR (RJR) - same | QFN-9 2.5x2 mm - different |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Input Voltage Range | 3 V to 36 V (42 V transient) | 3 V to 36 V | 3 V to 36 V | 3 V to 36 V (42 V transient) |
| Output Current | 4 A | 4 A | 6 A | 4 A |
| Qualification | AEC-Q100 (Q1) | Commercial grade | Commercial grade | AEC-Q100 (Q1) |
| Pin Compatible | Yes (family) | Yes | Yes | No (different package) |
| Light Load Mode | Pin selectable | Pin selectable | Pin selectable | Pin selectable |
Diferenciadores clave
- 42 V transient tolerance without external surge protection (frente a LM61440)
- Proprietary HotRod package lowers EMI (frente a LMR61440-Q1)
- Pin-compatible current scaling path (frente a LM61460)
Notas de diseño
Exploit the HotRod parallel input path by placing the input ceramic capacitor loop as tight as possible across PVIN and PGND. The package eliminates bond wires specifically to minimize parasitic inductance - long traces negate this benefit and raise switch-node ringing, degrading the low-EMI advantage. Follow the layout section of datasheet SNVSBE4C for recommended land pattern and via stitching to the ground plane.
Use the RT/SYNC pin to set the switching frequency away from sensitive bands (e.g., AM radio band 530-1700 kHz for automotive) and enable synchronization to a clean system clock when multiple converters operate nearby. The HotRod package already minimizes switch-node ringing, but snubber-free EMI compliance still requires a compact power stage and shielded or tightly-coupled inductor selection.
Use the MODE pin strap deliberately: light-load mode improves standby efficiency but introduces larger output ripple and variable frequency, which can upset sensitive analog rails downstream. For ADC/DAC analog supplies, force continuous conduction. Also confirm the BOOT capacitor is rated above the internal driver voltage and never leave EN floating in safety-critical rails - tie it through a divider for defined startup.
Información de cumplimiento
AEC-Q100 automotive qualification confirmed per TI product page. RoHS/REACH/lead-free status not stated in provided data - verify on TI quality pages.
