UM1350

UM1350 350mA, LED Lighting Driver UM1350 SOT23-5 General Description The UM1350 is capable of driving single or multiple series connected LEDs efficiently from a voltage source higher than the LED voltage. This step-down converter provides an externally adjustable output current of up to 350mA from an input supply between 6V and 30V. It can even reach 8 watts of output power, depending on supply voltage and external components. The UM1350 consists of an output switch and a high-side output current sensing circuit that uses an external resistor to set the nominal average output current. Through applying an external control signal to the VSET pin, it can adjust the output current below the set value. The VSET pin will accept either a DC voltage or a PWM waveform to provide a continuous or a gated output current. The chip contains a PWM filter which provides a soft-start feature by controlling the rise of input/output current. It can raise the soft-start by using an external capacitor f...