DIODES AL8866QSP-13

AL8866Q is a buck-boost, boost, buck, and SEPIC DC switching controller designed to drive external MOSFETs for high-power automotive LED applications such as automotive headlights. The device operates over a wide input supply voltage range of 4.7V to 85V. AL8866Q is based on a fixed-frequency, peak current mode control architecture combined with spread spectrum modulation technology to achieve low EMI performance. It supports LED current modulation via analog or PWM dimming techniques. By varying the DIM pin voltage, an analog dimming response with a linear range exceeding 100:1 can be achieved. PWM dimming is implemented by directly modulating the same DIM pin at the desired duty cycle. The device integrates a soft-start function that limits current through the inductor and external power switch during initial startup, gradually increasing inductor and switch current to minimize potential overvoltage and overcurrent risks at the output. Its open-drain fault output can indicate triggered protection conditions such as LED output overvoltage, LED output open/short circuit, cycle-by-cycle overcurrent protection, sense resistor and inductor/diode short circuit, diode open circuit, and thermal shutdown. AL8866Q is available in enhanced thermal dissipation SO-8EP and U-DFN3030-10 packages.

• AEC-Q100 compliant (Grade 1)
• Wide input voltage range: 4.7V to 85V
• Factory-preset 400kHz switching frequency
• Spread spectrum modulation for reduced EMI
• Analog dimming range: 1% to 100%
• Current accuracy ±3% at 100% dimming level
• Current accuracy ±12% at 20% dimming level
• PWM dimming ratio 100:1 at 200Hz PWM frequency
• Programmable soft-start
• Fault status indicator for protection state indication
• Output overvoltage and LED open-circuit protection
• Output undervoltage and LED short-circuit protection
• Cycle-by-cycle overcurrent limiting protection
• Sense resistor short-circuit protection
• Diode/inductor short-circuit protection
• Diode open-circuit protection
• Thermal shutdown protection
• Fully lead-free and RoHS compliant (Notes 1 and 2)
• Halogen-free and antimony-free. "Green" device (Note 3)
• Suitable for automotive applications requiring specific change control; this part is AEC-Q100 compliant, PPAP capable, and manufactured in an IATF 16949 certified facility.

• Automotive headlights
• High beam
• Low beam
• Daytime running lights (DRL)
• Fog lights, turn signals, and position lights