The DiodesZetex AL1665 is a high-performance single-stage fly back and buck boost controller, targeting dimmable LED lighting application. It is a primary side regulation (PSR) controller that can provide accurate constant current (CC) regulation without optocoupler 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. It can support analog/PWM dimming modes. The analog dimming range is 5% to 100%. The PWM dimming range is 0.5% to 100% (1k PWM dimming frequency). It comes in a SO-8 package. Valley switching for low switching loss Tight CS reference voltage 0.4V, ±1.5% Support analog and PWM dimming Integrates multiple internal protection