QX9920 Datasheet | QXMD

QX9920 Buck Type High-power LED Driver General Description QX9920 is a highly stable and reliable constant-current LED driver with high efficiency. It is especially suited to drive several high power and high luminance LEDs in series. QX9920 uses fixed off-time and peak current control mode and its operating frequency can vary up to 1MHz, which not only reduces the dimensions of inductor, capacitor and PCB but also improves efficiency. The minimum off-time is 620ns and the off-time can be adjusted by changing the external capacitor, and the operating frequency also can be adjusted according to the need of customers. QX9920 regulates the current flowing through LEDs to set the luminance of LEDs by changing the external resistor, and the current can vary from tens of m A to 2.5A, on the other hand, the luminance of LEDs also can be regulated by a PWM signal applied to EN pin. Features - Wide Range Input Voltage:2.5V to 100V - High Efficiency: Up to 90% - Maximum Operating Frequency: 1MHz - UVLO Voltage: 2.5V - Peak Current Sense Voltage: 250m V - Adjustable Luminance With PWM Signal Applied to EN Pin - Adjustable Off-time - Internal Current Sampling Leading Edge Blanking Circuit Applications - LED Backlight of Flat Panel Display - Bike Light - LED Spotlight - Very Bright Flashlight Typical Application L1 R1 CIN CVDD EN QX9920 TOFF VSS COFF QX9920_DS02EN Figure 1：Typical Application Circuit Diagram of QX9920 QX Micro Devices Co.,...