LM3481MMX/NOPB - 2.97V-48V Boost/SEPIC/Flyback Controller | TI
MPN: LM3481MMX/NOPB β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.52 | $1.52 |
| 10 | $1.36 | $13.60 |
| 100 | $1.09 | $109.00 |
| 500 | $0.92 | $460.00 |
| 1,000 | $0.78 | $780.00 |
Drop-in alternatives for LM3481MMX/NOPB β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
LM3481QMMX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM3478MMX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM3488MMX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM3478QMMX/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LT3757EMSE#PBF
β Drop-Inπ Reference alternative (not in catalog)
LM3481MMX/NOPB Maximum Ratings & Electrical Characteristics
| Topology | Boost, SEPIC, Flyback |
| Output Type | Positive |
| Input Voltage Range | 2.97 V to 48 V |
| Switching Frequency | Up to 1 MHz |
| PWM Type | Current Mode |
| Number of Outputs | 1 |
| Duty Cycle | 85% |
| Package | 10-VSSOP (DGS) |
| Operating Temperature Range | -40Β°C to 125Β°C |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel |
| RoHS Status | Compliant |
| REACH Status | Compliant |
| AEC-Q100 Qualified | No (standard version) |
| Lead-Free | Yes |
LM3481MMX/NOPB Pin Configuration
| Pin 1 | FB β Feedback input for output voltage regulation |
| Pin 2 | COMP β Compensation pin for loop stability |
| Pin 3 | ISENSE β Current sense input for cycle-by-cycle limiting |
| Pin 4 | GND β Ground |
| Pin 5 | DR β Gate drive output for external N-channel MOSFET |
| Pin 6 | VIN β Input supply voltage |
| Pin 7 | VCC β Internal regulated supply for control circuitry |
| Pin 8 | SD β Shutdown pin (active low) |
| Pin 9 | SYNC β Frequency synchronization input |
| Pin 10 | RT β Oscillator timing resistor connection |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
LM3481MMX/NOPB is suitable for 6 applications: Automotive Power Supplies, Industrial Power Systems, LED Lighting Drivers, Battery-Powered Devices, Telecom and Networking Equipment, Renewable Energy Systems.
Automotive Power Supplies
The LM3481MMX/NOPB's wide input range (2.97V to 48V) and ability to implement boost, SEPIC, and flyback topologies make it ideal for automotive power supplies. It can generate regulated rails from fluctuating battery voltages (e.g., 12V from 5V) or provide isolated supplies for sensors and ECUs. Its high switching frequency (up to 1MHz) allows for compact magnetics, saving PCB space in space-constrained automotive modules. The device's -40Β°C to 125Β°C operating range ensures reliable operation under extreme under-hood temperatures. For AEC-Q100 compliance, use the LM3481QMMX/NOPB variant.
Recommended
Industrial Power Systems
In industrial environments, the LM3481MMX/NOPB provides a robust solution for generating high-voltage rails from lower-voltage sources. Its current-mode control ensures stable operation under varying loads, which is critical for factory automation and process control equipment. The wide input range accommodates 24V and 48V industrial buses, while the adjustable switching frequency allows designers to optimize efficiency and EMI. The device's thermal shutdown and cycle-by-cycle current limiting protect against faults, enhancing system reliability. Its small VSSOP package is suitable for space-limited PLC and sensor modules.
Recommended
LED Lighting Drivers
The LM3481MMX/NOPB can be configured as a boost converter to drive high-power LEDs with constant current. Its high switching frequency (up to 1MHz) enables the use of small inductors, reducing the size of LED drivers for automotive headlights, industrial lighting, and backlighting. The current-mode control provides accurate current regulation, ensuring consistent brightness and preventing LED thermal runaway. The device's wide input range supports various supply voltages, from 12V automotive systems to 48V industrial lighting. External MOSFET selection allows scaling to high LED currents, making it a flexible solution for LED driver designs.
Recommended
Battery-Powered Devices
For battery-powered applications, the LM3481MMX/NOPB's low quiescent current and high efficiency extend battery life. It can boost a single-cell Li-ion voltage (3.0-4.2V) to a regulated 5V or 12V rail for portable electronics, IoT devices, and handheld instruments. The wide input range also accommodates multi-cell battery packs. The shutdown pin allows power gating to reduce standby current. Its small VSSOP package is ideal for compact, portable designs. The controller's ability to implement SEPIC topology is beneficial when the output voltage can be above or below the battery voltage, such as in USB power delivery.
Recommended
Telecom and Networking Equipment
In telecom and networking systems, the LM3481MMX/NOPB is used to generate intermediate bus voltages from a 48V backplane. Its boost and flyback capabilities enable isolated power supplies for line cards, routers, and switches. The high switching frequency reduces transformer size in flyback designs, saving board space. The device's current-mode control provides excellent line and load transient response, which is critical for digital loads. The wide input range (2.97V to 48V) makes it versatile for various telecom power architectures. The device's thermal performance ensures reliable operation in densely packed equipment racks.
Recommended
Renewable Energy Systems
The LM3481MMX/NOPB is well-suited for renewable energy systems such as solar charge controllers and wind power converters. Its wide input voltage range allows it to handle varying input from solar panels (e.g., 12V to 48V) and boost to a regulated bus voltage for battery charging or grid-tie inverters. The high-efficiency current-mode control maximizes energy harvest. The device's robust protection features (thermal shutdown, current limit) ensure reliable operation in outdoor environments. Its small package is beneficial for compact power optimizers and microinverters. The ability to implement SEPIC topology is useful for maximum power point tracking (MPPT) where output can be above or below input.
Recommended
Recommended Products Summary
Engineering reference data for LM3481MMX/NOPB β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM3481QMMX/NOPB | LM3478MMX/NOPB | LM3488MMX/NOPB | LT3757EMSE#PBF |
|---|---|---|---|---|---|
| Package | 10-VSSOP (DGS) | 10-VSSOP (DGS) | 10-VSSOP (DGS) | 10-VSSOP (DGS) | 10-MSOP |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Input Voltage Range | 2.97V to 48V | 2.97V to 48V | 2.97V to 40V | 2.97V to 48V | 4.5V to 40V |
| Switching Frequency | Up to 1MHz | Up to 1MHz | Up to 1MHz | Up to 1.5MHz | Up to 1MHz |
| Automotive Grade | No | Yes (AEC-Q100) | No | No | No |
| Frequency Synchronization | Yes | Yes | No | Yes | Yes |
| Maximum Duty Cycle | 85% | 85% | 85% | 85% | 90% |
| Price (1000 pcs) | $0.78 | $0.85 | $0.70 | $0.80 | $2.50 |
Key Differentiators
- Wide input voltage range up to 48V (vs LM3478MMX/NOPB)
- Frequency synchronization capability (vs LM3478MMX/NOPB)
- Automotive-grade variant available (vs LM3488MMX/NOPB)
Design Notes
For optimal performance, place the input capacitor, output capacitor, and the external MOSFET close to the LM3481MMX/NOPB. Use short, wide traces for high-current paths to minimize parasitic inductance and resistance. The gate drive trace should be kept short to reduce ringing. A solid ground plane is recommended to reduce noise and improve thermal performance.
The LM3481MMX/NOPB itself dissipates minimal power, but the external MOSFET and inductor may generate significant heat in high-power applications. Ensure adequate copper area and airflow around these components. The VSSOP package has a thermal resistance of approximately 150Β°C/W (theta_JA); keep the junction temperature below 125Β°C by providing a thermal path to the PCB.
A common mistake is improper loop compensation, leading to instability. Use the design equations in the datasheet to calculate the compensation network (COMP pin). Also, ensure the current sense resistor is placed correctly to avoid noise pickup. The SYNC pin should be tied to ground if not used to prevent erratic operation. Verify the external MOSFET's gate charge is compatible with the drive capability.
Compliance Information
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified; use LM3481QMMX/NOPB for automotive.
