LM3444 - AC-DC Offline LED Driver | Texas Instruments
MPN: LM3444 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.27 | $1.27 |
| 10 | $1.15 | $11.50 |
| 100 | $0.98 | $98.00 |
| 500 | $0.85 | $425.00 |
| 1,000 | $0.75 | $750.00 |
Drop-in alternatives for LM3444 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:
LM3444MM/NOPB
β Drop-Inπ Reference alternative (not in catalog)
LM3444M/NOPB
β Drop-Inπ Reference alternative (not in catalog)
NCL30000
β‘ Same Packageπ Reference alternative (not in catalog)
HV9910
β‘ Same Packageπ Reference alternative (not in catalog)
BP2832A
β‘ Same Packageπ Reference alternative (not in catalog)
LM3444 Maximum Ratings & Electrical Characteristics
| Topology | Buck (Step-Down) |
| Type | AC-DC Offline LED Driver |
| Output Current | Constant (set by external sense resistor) |
| Input Voltage Range | 90VAC to 265VAC |
| Switching Frequency | Up to 1 MHz |
| Power Factor | >0.9 (passive PFC) |
| Package Options | 10-pin VSSOP, 8-lead SOIC |
| Control Method | Adaptive Constant Off-Time |
| Internal Switch | 700V MOSFET (SOIC version) |
| Protection Features | Thermal Shutdown, Cycle-by-Cycle Current Limit |
| Operating Temperature Range | -40Β°C to +125Β°C |
| RoHS Status | Compliant |
| Mounting Type | Surface Mount |
| MSL Level | [DATA_NEEDED: MSL Level] |
| Package Dimensions | [DATA_NEEDED: Package Dimensions] |
LM3444 Pin Configuration
| Pin 1 | VIN β Input voltage from rectified AC |
| Pin 2 | GATE β Gate drive for external MOSFET (VSSOP version) |
| Pin 3 | CS β Current sense input |
| Pin 4 | GND β Ground |
| Pin 5 | DIM β Dimming control input |
| Pin 6 | VCC β Internal supply voltage |
| Pin 7 | NC β No connect |
| Pin 8 | NC β No connect |
| Pin 9 | NC β No connect |
| Pin 10 | NC β No connect |
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
LM3444 is suitable for 6 applications: LED Bulbs, LED Tubes, LED Downlights, Industrial Lighting, Commercial Lighting, Outdoor Lighting.
LED Bulbs
The LM3444 is ideal for LED bulbs, providing constant current to high-power LEDs with high efficiency and good power factor. Its adaptive constant off-time control ensures stable current over a wide input voltage range (90VAC to 265VAC), making it suitable for universal mains applications. The high-frequency operation (up to 1 MHz) allows the use of small inductors and capacitors, enabling compact bulb designs. The passive PFC circuit achieves a power factor greater than 0.9, meeting regulatory requirements for residential lighting. The device's thermal shutdown protection ensures reliable operation in enclosed bulb fixtures.
Recommended
LED Tubes
For LED tube lighting, the LM3444 provides a cost-effective solution with its passive PFC and high-frequency operation. The constant current output ensures uniform brightness across the LED string, while the wide input voltage range accommodates various line voltages. The small external component count reduces the overall system cost and size, making it suitable for retrofit LED tubes. The device's adaptive off-time control maintains efficiency across load variations, and the thermal shutdown feature protects against overheating in enclosed fixtures. The LM3444 can drive multiple LED strings in series, simplifying the design for tube applications.
Recommended
LED Downlights
The LM3444 is well-suited for LED downlights, where space is limited and efficiency is critical. Its high-frequency operation allows for a compact design with small magnetic components, fitting into tight downlight housings. The passive PFC ensures compliance with power quality standards, and the constant current output maintains consistent light output. The device's thermal shutdown protection is essential for downlights that operate in insulated ceilings. The wide input voltage range (90VAC to 265VAC) makes it versatile for global markets. The LM3444 can be used with an external MOSFET for higher power downlights, providing design flexibility.
Recommended
Industrial Lighting
In industrial lighting applications, the LM3444 offers robust performance with its wide input voltage range and thermal protection. The device can drive high-power LEDs used in warehouses, factories, and street lighting. The passive PFC circuit helps meet IEC 61000-3-2 Class C harmonic limits, which are often required for commercial and industrial lighting. The high-frequency operation reduces the size of passive components, lowering the overall system cost. The constant current output ensures consistent light output over time, reducing maintenance costs. The LM3444's adaptive off-time control provides stable operation under varying line conditions, making it reliable for industrial environments.
Recommended
Commercial Lighting
For commercial lighting, such as office buildings and retail spaces, the LM3444 provides a high-performance solution with good power factor and efficiency. The passive PFC ensures compliance with energy efficiency regulations, and the constant current output maintains consistent brightness for a professional lighting environment. The device's small footprint and low component count make it easy to integrate into lighting fixtures. The wide input voltage range allows for use in different countries without modification. The LM3444's thermal shutdown protection ensures safe operation in enclosed fixtures, and its high-frequency operation reduces electromagnetic interference, which is important for commercial settings.
Recommended
Outdoor Lighting
The LM3444 is suitable for outdoor lighting applications, such as streetlights and parking lot lights, where reliability and efficiency are paramount. The device's wide input voltage range (90VAC to 265VAC) accommodates various grid conditions, and its passive PFC helps meet power quality standards. The constant current output ensures consistent light output over a wide temperature range, which is critical for outdoor environments. The high-frequency operation allows for a compact design that can be sealed in weatherproof enclosures. The LM3444's thermal shutdown protection prevents damage from high ambient temperatures, and its robust design ensures long-term reliability in harsh conditions.
Recommended
Recommended Products Summary
Engineering reference data for LM3444 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM3444MM/NOPB | LM3444M/NOPB | NCL30000 | HV9910 |
|---|---|---|---|---|---|
| Package | 10-pin VSSOP / 8-lead SOIC | 10-pin VSSOP | 8-lead SOIC | SOIC-8 | SOIC-8 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | onsemi | Microchip Technology |
| Control Method | Adaptive Constant Off-Time | Adaptive Constant Off-Time | Adaptive Constant Off-Time | Critical Conduction Mode | PWM |
| Input Voltage Range | 90VAC to 265VAC | 90VAC to 265VAC | 90VAC to 265VAC | 85VAC to 265VAC | 8V to 450V DC |
| Switching Frequency | Up to 1 MHz | Up to 1 MHz | Up to 1 MHz | Variable (CrM) | Up to 300 kHz |
| Power Factor Correction | Passive PFC | Passive PFC | Passive PFC | Active PFC | None |
| Internal Switch | 700V MOSFET (SOIC version) | External MOSFET required | 700V MOSFET | External MOSFET | External MOSFET |
| Dimming Support | Yes (analog/PWM) | Yes (analog/PWM) | Yes (analog/PWM) | Yes (PWM) | Yes (PWM) |
Key Differentiators
- Adaptive constant off-time control (vs HV9910)
- Passive PFC included (vs HV9910)
- High-frequency operation up to 1 MHz (vs NCL30000)
Design Notes
The LM3444 can dissipate significant power, especially in the SOIC package with internal MOSFET. Ensure adequate copper area on the PCB for heat sinking. For high-power applications, consider using the VSSOP version with an external MOSFET to distribute heat. The thermal shutdown feature protects the device, but proper thermal design is essential for reliable operation.
Place the input capacitor, inductor, and sense resistor close to the LM3444 to minimize parasitic inductance and ensure stable operation. Use a ground plane to reduce noise and improve thermal performance. The high-frequency switching (up to 1 MHz) requires careful layout to minimize EMI. Follow the layout guidelines in the datasheet for optimal performance.
Ensure the sense resistor is properly rated for the power dissipation. Incorrect sense resistor selection can lead to inaccurate output current or overheating. Also, verify that the inductor saturation current is higher than the peak current to avoid core saturation. The passive PFC circuit requires a valley-fill capacitor; ensure it is properly sized to maintain power factor.
Compliance Information
RoHS compliant per TI product page. Lead-free (NOPB) variants available. Not AEC-Q100 qualified.
