By Diodes Incorporated 35
The Diodes Inc. AL8807A is a step-down, DC/DC converter designed to drive LEDs with a constant current. The device can drive up to 9 white high brightness LEDs in series from a voltage source of 6 V to 36 V. The AL8807A has an extended CTRL pin voltage range, increasing its analog dimming range to greater than 10:1. The improved analog dimming range makes it suitable for a variety of lighting applications requiring wide analog dimming ranges. The AL8807A switches at frequency up to 1 MHz with controlled rise and fall times to reduce EMI. This allows the use of small size external components, hence minimizing the PCB area needed. Maximum output current of AL8807A is set via an external resistor connected between the VIN and SET input pins. Over-temperature protection is incorporated so that should a fault occur, the device will automatically shut-down and only restart when its junction temperature has cooled down.