KB4312裕鼎祥咨询电话：139 2843 4054
KB4312 DESCRIPTION
The KB4312 step-up converter drives white LEDs with a constant current to provide backlight in cell phones, PDAs, and other hand-held devices. KB4312 features allowing series connection of the white LEDs so that the LED currents are identical for uniform brightness. An enable input can be pulsed repeatedly to adjust LED’s brightness. The fast 1.2MHz current-mode PWM control allows for smaller capacitor and inductor. Fault condition protection uses cycle-by-cycle current limiting to sense maximum inductor current, thermal protection and over-voltage protection. Also included soft-start eliminates inrush current during start-up. The 0.24V low reference voltage minimized the power loss across the current-setting resistor.The KB4312 is available in SOT23 packages。
KB4312 FEATURES
•KB4312 Operating Voltage:2.5V~6.5V
•KB4312 High Operating Frequency: 1.2MHz
•KB4312 High Output Voltage: Up to 28V(max)
•KB4312 Shutdown Current <1uA
•KB4312 18V Output Over-voltage protection (ADJ)
•KB4312 Digital Dimming Control.
•KB4312 Built-in Cycle-by Cycle Current-limiting.
•KB4312 Built-in Soft-Start Function.
•KB4312 0.24V Low Reference Voltage(+/-5%)
•KB4312 Tiny SOT23 Package
KB4312 Applications
• LED Module
• LED Backlight for LCD Display (1 ~6.5 )
• Constant Current Source
