The HV9910BLG-G is an open loop current mode Control LED Driver IC programmed to operate in either a constant frequency or constant off-time mode. It includes an 8 to 450V linear regulator allows it to work from a wide range of input voltages without the need for an external low voltage supply. The HV9910B includes a PWM dimming input that can accept an external control signal with a duty ratio of 0 to 100% and a frequency of up to a few kilohertz. It also includes a 0 to 250mV linear dimming input which can be used for linear dimming of the LED current. The HV9910B is ideally suited for buck LED drivers. Since the HV9910B operates in open loop current mode control, the controller achieves good output current regulation without the need for any loop compensation. PWM dimming response is limited only by the rate of rise and fall of the inductor current, enabling very fast rise and fall times.