AS3490

valid Datasheet AS3490 Highly Efficient 2-6 LEDs Backlight Driver with PWM Input 1 General Description The AS3490 is an inductive highly efficient DCDC boost converter. The DCDC converter operates at a fixed frequency of 2MHz and includes soft startup to allow easy integration into noise sensitive RF systems. A predictable startup is guaranteed even with very low duty cycle PWM input signals. The voltage on the output capacitor is controlled to minimize ripple and to avoid any acoustic effects for low frequency PWM input signals. The output of the DCDC converter is used for five current sources connected to up to 6 LEDs. If a current source is not required, it shall be connected to VOUT or GND - the AS3490 detects this condition and disables this current source automatically; this keeps the efficiency of the system constantly high. The AS3490 is controlled by one enable input, ON. This input can also be used to connect a PWM input (like DLS or DBC). The AS3490 includes several protection functions like undervoltage lockout, overcurrent and overtemperature. No microvias are required to assemble the AS3490. The AS3490 is available in a space-saving WL-CSP package measuring only 1.7x1.4x0.5mm and operates over the -30ºC to +85ºC temperature range. Figure 1. AS3490 Typical Operating Circuit 2 Key Features 2 MHz DCDC Boost converter - Small 4.7µH external coil - Very high system efficiency of 86% (DCDC and current sources combined) - Very low voltage changes on output to avo...