The SFL850 uses a “Boost-PFC/Buck ComboTM” combined control architecture, integrating a boost PFC and a buck constant current controller, suitable for non-isolated LED lighting applications. This 8-pin chip boasts high integration and requires minimal external components. It achieves a constant current accuracy within 5%, a high power factor, and low THD, while completely eliminating the flicker defects of single-stage BUCK-PFC. The SFL850's PFC stage does not require detection of the input rectified sine wave to achieve PFC functionality. The chip incorporates patented “NC-Aux/PFCTM” technology, eliminating the need for a demagnetization detection winding and enabling critical conduction mode operation of the inductor, supporting the use of a single-winding inductor. The SFL850 PFC stage also incorporates patented “Min-THDTM” technology to achieve THD<15%. It also includes soft-drive technology, significantly improving system EMI performance compared to quasi-resonant control modes. The SFL850's buck stage uses quasi-resonant control, resulting in high efficiency and eliminating the need for external inductor inductance compensation, achieving high-precision constant current. The SFL850 also integrates numerous protection functions, such as: VCC undervoltage protection (UVLO), VCC overvoltage protection, cycle-by-cycle overcurrent protection, GATE output voltage clamping protection, LED short-circuit/open-circuit protection, and overtemperature frequency reduction. The SFL850 is available in an SOP8 package.

◆ 8 PIN Solution, high integration, high performance, very few peripheral devices

◆ “ Boost-PFC/Buck Combo ^TM  ” Combination control

◆ Built-in 1% Accuracy (@Tj=25 ℃ ) Constant current reference voltage

◆ Two-stage control, completely eliminates single-stage PFC Flicker defects

◆ PFC Level built-in patented “ Min-THD ^TM ” Technical implementation PF>0.95 ， THD<15%

◆ PFC Level does not require detection of input rectified sine wave

◆ PFC Level cycle-by-cycle current limit

◆ PFC Level built-in patented “ NC-Aux/PFC ^TM Technology, no demagnetization detection winding required, supports the use of single winding inductor

◆ PFC Level built-in patented “Fast Dynamic response Technology, improve PFC Loop dynamic response

◆ Buck Level uses quasi-resonant control to achieve high efficiency

◆ Buck Level does not require external inductor inductance compensation, achieving high-precision constant current

◆ Buck Level built-in patented “ NC-Aux/Buck ^TM Technology, no demagnetization detection winding required, supports the use of single winding inductor

◆ Buck Level built-in patented over-temperature frequency reduction function, no flicker at over-temperature

◆ LED Open Circuit / Short circuit protection

◆ Built-in leading edge blanking

◆ VDD UVLO (Undervoltage protection)

◆ VDD Overvoltage protection ( OVP ) and clamping

Application

◆ Flicker-free LED Lighting occasions