MP2451DJ-LF-P - 600mA, 36V, 2MHz Step-Down Converter | MPS
N.º de pieza: MP2451DJ-LF-P ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $0.95 | $0,95 |
| 10 | $0.85 | $8,50 |
| 100 | $0.72 | $72,00 |
| 500 | $0.58 | $290,00 |
| 1.000 | $0.48 | $480,00 |
| 3.000 | $0.42 | $1.260,00 |
MP2451DJ-LF-P Descripción general
What is a buck (step-down) switching regulator? A buck converter is a type of switched-mode power supply (SMPS) that efficiently steps a higher DC input voltage down to a lower DC output voltage. It belongs to the DC-DC converter hierarchy -> power management IC -> semiconductor. Compared to linear regulators, buck converters achieve much higher efficiency (often above 90 %) at the cost of output ripple and the need for an external inductor and capacitors. The MP2451 integrates the high-side MOSFET and control loop into one IC, simplifying PCB design and shrinking the BOM.
Key features include a wide 3.3 V to 36 V input range (well-suited to automotive 12 V/24 V buses), 600 mA continuous output current, 2 MHz fixed switching frequency (allowing small ceramic output capacitors and a compact inductor), internal compensation, internal soft-start, cycle-by-cycle over-current protection, and thermal shutdown. The TSOT-23-6 footprint is one of the smallest 600 mA synchronous-buck packages available, enabling high power density in space-constrained designs.
Technically, the MP2451 uses peak current-mode control with internal slope compensation, providing stable operation across duty cycles and easy loop compensation. The 2 MHz switching frequency pushes the fundamental and harmonics well above the AM broadcast band, simplifying EMI compliance in automotive and consumer products. The high-side P-channel MOSFET is fully integrated, eliminating the need for an external Schottky diode and reducing conduction loss.
Typical applications include automotive infotainment and instrument-cluster rails, distributed 5 V/3.3 V supplies from a 12 V or 24 V bus, USB/wall-adapter powered portable electronics, point-of-load conversion for microcontrollers and sensors, and battery-powered industrial equipment. The 36 V input tolerance also tolerates load-dump transients seen in automotive environments.
When designing with the MP2451, choose a low-DCR shielded inductor in the 2.2 uH to 4.7 uH range and use X7R ceramic input/output capacitors rated for the working voltage. Always observe the absolute-maximum VIN of 38 V and provide adequate PCB copper area for thermal dissipation at high VIN-VOUT differentials.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, giving an engineer a single decision-ready view of the MP2451DJ-LF-P.
Alternativas directas para MP2451DJ-LF-P — 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 MP2451DJ-LF-P (mismo factor de forma y huella) — difiere en Output Voltage Range, Package, Quiescent Current (Shutdown), RoHS Status, Soft Start.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MP2451DJ-LF-Z
✅ Sustitución directa✓ En stock
$0.2953 / unidad
Ver hoja de datos →MP2451DT-LF-P
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
MP2451DT-LF-Z
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
MP2451DJ-LF-P Valores máximos y características eléctricas
| Topología | Buck (Step-Down) Switching Regulator |
| Rango de tensión de entrada | 3.3 V to 36 V |
| Absolute Maximum VIN | 38 V |
| Rango de tensión de salida | 0.8 V to VIN (adjustable) |
| Output Current | 600 mA continuous |
| Frecuencia de conmutación | 2 MHz typical |
| Quiescent Current (Shutdown) | 1 uA |
| Control Method | Current-mode PWM |
| MOSFET | Internal high-side |
| Rectificador síncrono | No (non-sync, external diode) |
| Rango de temperatura de funcionamiento | -40 C to +125 C (junction) |
| Encapsulado | SOT-23-6 Thin (TSOT-23-6) |
| Tipo de montaje | Surface Mount |
| Estado RoHS | Compliant (LF suffix) |
| Lead-Free Finish | Yes (LF suffix) |
| Enable / Shutdown | Yes |
| Arranque suave | Internal |
| Protection Features | Over-current, thermal shutdown |
Configuración de pines de MP2451DJ-LF-P
| Pin 1 | SW — Switching node - connects to external inductor and Schottky diode cathode |
| Pin 2 | IN — Input supply voltage (3.3 V to 36 V) |
| Pin 3 | EN — Enable input; pull high to turn on, low for 1 uA shutdown |
| Pin 4 | FB — Feedback voltage input; 0.8 V reference, set VOUT with resistor divider |
| Pin 5 | GND — Ground return |
| Pin 6 | BST — Bootstrap; connect a small flying cap between BST and SW for high-side drive |
Aplicaciones típicas
MP2451DJ-LF-P es adecuado para 6 aplicacións: Automotive 12 V / 24 V Point-of-Load, Industrial 24 V Sensor / PLC Rails, Portable Battery-Powered Devices, USB / Wall-Adapter Powered Accessories, E-Metering and Energy Harvesting, LED Lighting Drivers.
Automotive 12 V / 24 V Point-of-Load
The MP2451DJ-LF-P fits automotive point-of-load conversion directly because its 3.3 V to 36 V input and 38 V abs-max survive cold-crank and load-dump on a 12 V or 24 V automotive bus, while its 600 mA output comfortably powers an MCU or sensor cluster. Placed after a front-end filter, the part steps the bus down to a clean 3.3 V or 5 V rail using a 2.2 uH shielded inductor and X7R ceramic caps, and the 2 MHz switching frequency keeps EMI above the AM band. Compared with an LDO, the buck topology keeps efficiency above 90 percent, which is critical for body-control modules that sit on the battery rail continuously.
Recomendado
Industrial 24 V Sensor / PLC Rails
The MP2451DJ-LF-P is well matched to industrial 24 V PLC and sensor modules because its 36 V input tolerates the worst-case rectified 24 V bus including transients, and its 600 mA output can run multiple analog and digital loads in parallel. Designed in with current-mode control and internal compensation, the loop is stable with ceramic output capacitors, eliminating bulky electrolytics on crowded PLC boards. The 1 uA shutdown quiescent current is valuable for remote sensors that spend most of their life asleep between measurements, and the wide -40 C to +125 C thermal rating supports outdoor enclosures and factory-floor temperature swings.
Recomendado
Portable Battery-Powered Devices
The MP2451DJ-LF-P suits portable, battery-powered products thanks to its 1 uA shutdown quiescent current and high efficiency at light load, which together extend runtime on a single-cell Li-ion or 2x AA pack. Its 2 MHz switching frequency enables a tiny 2.2 uH inductor and small ceramic capacitors, freeing board area for the rest of a handheld design. Compared with an LDO at the same load, the buck typically saves several mW of dissipation, directly translating to longer standby time. Designers should add an input Schottky or fuse for reverse-battery and hot-plug protection typical in consumer portable designs.
Recomendado
USB / Wall-Adapter Powered Accessories
The MP2451DJ-LF-P is ideal for USB-powered or wall-adapter-powered accessories because its 3.3 V minimum input starts up directly from a 5 V USB rail, and its 36 V tolerance allows the same board to be powered from unregulated 12 V adapters without redesign. At 2 MHz the fundamental ripple is far above typical audio or data-acquisition bandwidth, so the post-buck noise floor is set by the load rather than the regulator. The TSOT-23-6 footprint keeps the converter small enough to sit next to a USB-C connector, making it a clean choice for dongles and docking stations.
Recomendado
E-Metering and Energy Harvesting
The MP2451DJ-LF-P fits e-metering and energy-harvesting front ends because its wide 3.3 V to 36 V input accepts rectified mains or solar inputs, and its 1 uA shutdown current preserves battery-backed RTC and metrology circuits between active windows. The 2 MHz switching frequency is well above the metrology ADC sampling band, simplifying post-filtering, and current-mode control provides excellent line transient response for load steps caused by relay switching in smart meters. Designers should pair the MP2451 with a low-Iq MCU supervisor and a precision metrology ADC for a complete energy-measurement subsystem.
Recomendado
LED Lighting Drivers
The MP2451DJ-LF-P is a good fit for driving constant-current LED strings from a 12 V or 24 V bus because its 600 mA output can power multiple high-brightness LEDs in series and its adjustable output from 0.8 V upward allows a simple sense-resistor feedback loop. The 36 V input withstands the inductive kick of long LED wiring harnesses, and the 2 MHz switching frequency is well above the human flicker-fusion threshold, producing visually flicker-free light even at low dimming levels. Thermal performance in the TSOT-23-6 package is sufficient for LED currents up to about 350 mA continuous without external heatsinking.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MP2451DJ-LF-P — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MP2451DJ-LF-Z | MP2451DT-LF-P | MP2451DT-LF-Z |
|---|---|---|---|---|
| Package | TSOT-23-6 | TSOT-23-6 - same | TSOT-23-8 | TSOT-23-8 |
| Brand | Monolithic Power Systems | Monolithic Power Systems | Monolithic Power Systems | Monolithic Power Systems |
| Input Voltage Range | 3.3 V to 36 V | 3.3 V to 36 V | 3.3 V to 36 V | 3.3 V to 36 V |
| Output Current | 600 mA | 600 mA | 600 mA | 600 mA |
| Switching Frequency | 2 MHz | 2 MHz | 2 MHz | 2 MHz |
| Output Voltage Range | 0.8 V to VIN | 0.8 V to VIN | 0.8 V to VIN | 0.8 V to VIN |
| Shutdown Iq | 1 uA | 1 uA | 1 uA | 1 uA |
| Synchronous Rectifier | No (external Schottky) | No (external Schottky) | No (external Schottky) | No (external Schottky) |
| Pin/Package Variant | TSOT-23-6, P reel | TSOT-23-6, Z reel | TSOT-23-8, P reel | TSOT-23-8, Z reel |
Diferenciadores clave
- Widest input range in the small TSOT-23-6 buck class (frente a MP2459GJ-P)
- Smallest package for 600 mA at 36 V (frente a MP2451DT-LF-P)
- Very low 1 uA shutdown Iq (frente a MP2451DT-LF-P)
Notas de diseño
Place the input ceramic capacitor (>= 4.7 uF X7R), the Schottky diode, and the output inductor as close as possible to the SW and GND pins. The exposed pad on the TSOT-23-6 must be soldered to a ground copper pour of at least 50 mm^2 to keep the junction temperature within the -40 C to +125 C rating. Keep the FB trace away from the SW node and the inductor to avoid noise coupling into the feedback loop.
At VIN = 24 V, VOUT = 5 V, IOUT = 600 mA, the dissipation is about (24 - 5) V x 0.6 A x (1 - efficiency) plus switching loss. Estimated: with ~90% efficiency the IC dissipation is around 1.1 W, which the TSOT-23-6 can handle only with a substantial copper pour or forced airflow. Drop the input voltage or reduce load at high VIN to stay within thermal limits.
Do not omit the BST flying capacitor between BST and SW; without it the high-side MOSFET will not turn on fully and efficiency drops sharply. Do not drive large MOSFET gates from BST; it is rated only for the internal high-side driver. Always respect the 38 V absolute-max VIN, including transients; add a TVS or input fuse if the source is a long automotive harness.
The fixed 2 MHz switching frequency keeps fundamental emissions above the AM broadcast band, but switching-node ringing can still violate CISPR 25 in sensitive automotive designs. Add a small RC snubber (~ 2 to 10 ohm in series with 100 pF to 1 nF) across the Schottky diode or use a shielded inductor to damp SW-node ringing and reduce radiated emissions.
Información de cumplimiento
LF suffix indicates lead-free / RoHS compliant finish per MPS product page. Industrial-grade temperature range; not AEC-Q100 qualified - choose an automotive-qualified MPS part for safety-critical designs. Halogen-free status not explicitly stated in the verified data - marked unknown.
