The RT8480 is a current mode PWM controller designed to drive an external MOSFET for high current LED applications. With a low side current sense amplifier threshold of 190mV, the LED current is programmable with one external current sense resistor.
With programmable operating frequency up to 800kHz, the external inductor and capacitors can be small while maintaining high frequency.
Dimming can be done by either analog or digital. A built-in clamping comparator and filter allow easy low noise analog dimming conversion from digital signal with only one external capacitor. An unique True PWM dimming control is made easy with MOSFET under LED string. A very high dimming ratio can be achieved by adopting both analog/digital dimming and True PWM dimming together.
The RT8480 is available in a SOP-16 package.

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SOP-16

Figure 1. Analog Dimming in Boost Configuration

Figure 2. PWM to Analog Dimming in Boost Configuration

Figure 3. True PWM Dimming in Boost Configuration

Figure 4. Constant Voltage Output of Boost Converter

Figure 5. Constant Voltage Output of SEPIC Converter