National’s PowerWise LED drivers such as the LM34xx/LM340x/LM35xx families offer a maximum power-to-performance ratio, which means you get more features than standard incandescent and fluorescent lighting solutions at a fraction of the wattage. Using National’s PowerWise LED drivers, results in energy-efficient solutions that reduce power consumption.
The LM3421/LM3423 devices are versatile high voltage LED driver controllers. With the capability to be configured in a Buck, Boost, Buck-Boost (Flyback), or SEPIC topology, and an input operating voltage rating of 75 V, these controllers are ideal for illuminating LEDs in a very diverse, large family of applications.
Key Features
- VIN range from 4.5 V to 75 V
- 2% Internal reference voltage (1.235 V)
- Current sense voltage adjustable from 20 mV
- High-side current sensing
- 2 Ω MOSFET gate driver
- Dimming MOSFET gate driver
- Input under-voltage protection
- Over-voltage protection
- Low shutdown current, I Q < 1 µA
- Fast (50 kHz) PWM dimming
- Cycle-by-cycle current limit
- Programmable switching frequency
- LED output status flag (LM3423 only)
- Fault timer pin (LM3423 only)
- TSSOP EP 16-lead package (LM3421)
- TSSOP EP 20-lead package (LM3423)
Applications