Diodes Inc. — AL1673: Universal Flyback and Buck-Boost Single Stage Dimmable LED Driver

The AL1673 is a high-performance single stage LED driver-converter operating in flyback and buck-boost topologies, targeting dimmable LED lighting applications. It operates in BCM mode which results in good EMI and efficiency. It supports analog and PWM dimming modes. When a 0.3~2.4V DC signal is applied on APWM pin, the device will operate in analog dimming mode. When a digital signal is applied on APWM pin, the device works at PWM dimming mode. The AL1673 features low start-up current and low operating current. It integrates multiple protection functions including overvoltage, short-circuit, overcurrent and overtemperature protection.


  • Valley switching for low switching loss
  • High PF and low THD
  • Tight LED current variation range
  • Integrates 600V/2A MOSFET
  • 3% to 100% at 1kHz PWM dimming range
  • OVP, OCP, OTP protection features
  • 0.8μA start-up current
  • High efficiency
  • Tight output open voltage variation range
  • Thermal fold-back protection
  • Under voltage lock out
  • SO-8EP package