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The AL1665 is a high performance single stage flyback and buckboost controller, targeting dimmable LED lighting application. It is a Primary Side Regulation (PSR) controller which can provide accurate Constant Current (CC) regulation without opto-coupler and secondary control circuitry. It can be operated at BCM mode which results in low EMI and high efficiency, and keeps high Power Factor (PF) and low Total Harmonic Distortion (THD) under universal input voltage.

The AL1665 can support analog/PWM dimming modes. When a 50mV to 2.5V DC signal is applied on ADIM pin, the device will be operated in analog dimming mode. The analog dimming range is 5% to 100%. When a PWM signal is applied to NTC/PWM pin, the device will be operated at PWM dimming mode. The PWM dimming range is 0.5% to 100% (1k PWM dimming frequency).

The AL1665 features low operation current. It integrates multiple protections including overvoltage, short circuit, overcurrent and over-temperature.

The AL1665 is available in SO-8 (Standard) package.


  • General LED Lighting Driver with Dimming Function
  • General Purpose Constant Current Source
  • LED Backlighting Driver
  • Smart LED Lighting


  • Primary Side Regulation without Opto-Coupler
  • Valley Switching for Low Switching Loss
  • Low Start-Up Current
  • Support Analog and PWM Dimming
  • Analog Dimming Range: 5% to 100%
  • PWM Dimming Range: 0.5% to 100% (1k PWM Frequency)
  • Internal Protections
  • Under Voltage Lock Out (UVLO)
  • Output Over Voltage Protection (OVP)
  • Output Short Protection (OSP)
  • Over Current Protection (OCP)
  • CS Short Protection
  • Winding Short Circuit Protection
  • Secondary Diode Short Protection
  • Shorted Current Sense Protection
  • User Programmable NTC Based Thermal Foldback
  • Internal Thermal Fold-Back Protection (TFP)
  • Over Temperature Protection (OTP)
  • Low System Cost
  • High PF>0.9 and Low THD<20%
  • High Efficiency
  • Tight LED Current Variation Range
  • LED Current Line Regulation: ±2%
  • LED Current Load Regulation: ±2% Full Load to Half Load
  • Tight Output Open Voltage Variation Range
  • Package: SO-8 (Standard)

Product Specifications

Product Parameters

Minimum Input AC Voltage (VAC) 85
Maximum Input AC Voltage (VAC) 305
Maximum DC VDD (VDC) 18.5
LED Current (mA) External MOSFET
Frequency (kHz) 80K
Accuracy 1.5 %
Efficiency > 85 %
Dimming PWM, Analog
Supply Current 2 mA
Temperature Range '-40 to +105 °C

Technical Documents

Evaluation Boards and User Guides

SPICE/IBIS Model Documents


Recommended Soldering Techniques


Orderable Part Number Buy from Distributor / Contact Sales Request Samples


Authorized Distributor Quantity Inventory Date Countries/Regions Buy Online
Digi-Key Electronics 4 11/23/2020 Europe, Asia, North America Buy Now
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Authorized Distributor Quantity Inventory Date Countries/Regions Buy Online
Arrow Electronics Central EU 4000 11/23/2020 Europe Buy Now
Digi-Key Electronics 2910 11/23/2020 Europe, Asia, North America Buy Now
Mouser Electronics Inc. 7960 11/23/2020 South America, North America, Asia, Europe, Middle East Buy Now
Avnet 24000 11/22/2020 United States Buy Now
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