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)
LM3445
β‘ Same Packageπ Reference alternative (not in catalog)
HV9910
β‘ Same Packageπ Reference alternative (not in catalog)
AL8860
β‘ Same Packageπ Reference alternative (not in catalog)
LM3444 Maximum Ratings & Electrical Characteristics
| Topology | Buck (Step-Down) |
| Type | AC-DC Offline LED Driver |
| Input Voltage Range | 90VAC to 265VAC |
| Switching Frequency | Up to 1 MHz |
| Output Current | Constant (set by external sense resistor) |
| Power Factor | >0.9 (passive PFC) |
| Internal MOSFET | 700V (SOIC version) |
| Control Scheme | Adaptive Constant Off-Time |
| Package Options | 10-pin VSSOP, 8-lead SOIC |
| Operating Temperature Range | -40C to +125C |
| Thermal Shutdown | Yes |
| Cycle-by-Cycle Current Limit | Yes |
| Harmonic Distortion | Meets IEC 61000-3-2 Class C |
| RoHS Status | Compliant |
| Mounting Type | Surface Mount |
LM3444 Pin Configuration
| Pin 1 | VIN β Input voltage from rectified AC |
| Pin 2 | GATE β Gate drive for external MOSFET (VSSOP) |
| Pin 3 | ISENSE β Current sense input |
| Pin 4 | GND β Ground |
| Pin 5 | COFF β Off-time control |
| Pin 6 | VCC β Internal supply |
| Pin 7 | PFC β Power factor correction |
| Pin 8 | DIM β Dimming input (if available) |
| 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 provides constant current to drive high-power LEDs in retrofit bulbs. Its adaptive constant off-time control maintains stable current across 90-265VAC mains, ensuring consistent brightness. The high-frequency operation (up to 1 MHz) allows compact magnetics, fitting the tight space of A19 bulbs. Passive PFC achieves >0.9 power factor, meeting regulatory requirements. With thermal shutdown, it protects the LED module from overheating, extending bulb life.
Recommended
LED Tubes
For linear LED tubes, the LM3444's buck topology efficiently steps down rectified AC to drive LED strings. Its wide input range handles 120V and 230V mains without modification. The constant current output ensures uniform light output across the tube, preventing hot spots. The device's high switching frequency reduces inductor size, enabling slim tube designs. Passive PFC helps meet energy efficiency standards for commercial lighting.
Recommended
LED Downlights
The LM3444 is ideal for downlights where high efficiency and small size are critical. Its constant off-time control provides excellent line and load regulation, maintaining consistent brightness even with input voltage fluctuations. The device's thermal shutdown protects the driver and LED module in enclosed fixtures. With a power factor >0.9, it complies with commercial building codes. The high-frequency operation allows the use of small, low-profile inductors suitable for recessed lighting.
Recommended
Industrial Lighting
In industrial high-bay and street lighting, the LM3444 provides robust constant current drive for high-power LEDs. Its wide input range (90-265VAC) accommodates various industrial mains supplies. The device's cycle-by-cycle current limit and thermal shutdown ensure reliable operation in harsh environments. Passive PFC reduces harmonic distortion, meeting IEC 61000-3-2 Class C limits. The high switching frequency allows for smaller, more efficient magnetic components, reducing overall system cost.
Recommended
Commercial Lighting
For commercial lighting systems, the LM3444 offers a cost-effective solution with good power factor and low harmonic distortion. Its adaptive constant off-time control simplifies design and reduces component count. The device supports universal input, making it suitable for global products. The high-frequency operation enables small external components, reducing PCB area and BOM cost. Thermal shutdown ensures safety in enclosed fixtures, meeting UL and IEC requirements.
Recommended
Outdoor Lighting
The LM3444 is suitable for outdoor lighting such as streetlights and parking lot lights. Its wide input voltage range handles voltage fluctuations common in outdoor installations. The device's robust protection features, including thermal shutdown and cycle-by-cycle current limit, ensure long-term reliability. Passive PFC helps meet utility requirements for power quality. The high switching frequency allows for compact, weatherproof enclosures.
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 | LM3445 | HV9910 | AL8860 |
|---|---|---|---|---|---|---|
| Package | 10-pin VSSOP / 8-lead SOIC | 10-pin VSSOP | 8-lead SOIC | 10-pin VSSOP | 8-lead SOIC | 8-lead SOIC |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Microchip Technology | Diodes Incorporated |
| Input Voltage Range | 90VAC to 265VAC | 90VAC to 265VAC | 90VAC to 265VAC | 90VAC to 265VAC | 8V to 450V DC | 5V to 60V DC |
| Switching Frequency | Up to 1 MHz | Up to 1 MHz | Up to 1 MHz | Up to 1 MHz | Up to 300 kHz | Up to 1 MHz |
| Power Factor Correction | Passive, >0.9 | Passive, >0.9 | Passive, >0.9 | Active, >0.95 | None | None |
| Internal MOSFET | 700V (SOIC version) | External | 700V internal | External | External | Internal 60V |
| Control Scheme | Adaptive Constant Off-Time | Adaptive Constant Off-Time | Adaptive Constant Off-Time | Adaptive Constant Off-Time | Hysteretic | Hysteretic |
| Thermal Shutdown | Yes | Yes | Yes | Yes | No | Yes |
Key Differentiators
- Passive PFC achieves >0.9 power factor without active controller (vs HV9910)
- High switching frequency up to 1 MHz (vs HV9910)
- Internal 700V MOSFET in SOIC version (vs AL8860)
Design Notes
The LM3444 in SOIC package has an internal 700V MOSFET that dissipates significant power. Ensure adequate copper area on the PCB for heat sinking. For high-power applications, consider the VSSOP version with an external MOSFET to distribute heat. Refer to the datasheet thermal impedance values for proper design.
Place the sense resistor close to the ISENSE pin to minimize parasitic inductance. Use a low-ESR capacitor at VCC to filter noise. The high-frequency switching (up to 1 MHz) requires careful layout to reduce EMI; keep the switch node small and use a ground plane.
Do not exceed the absolute maximum ratings for VIN and VCC. Ensure the off-time capacitor is correctly sized to maintain constant current over the full input range. Incorrect component selection can lead to LED current variation and reduced efficiency.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified.
