Light emitting device driving apparatus and illumination system including the same

摘要

Disclosed is a light emitting device driving apparatus configured to control a light emitting unit including light emitting devices or array(s) thereof connected in series. The light emitting device driving apparatus includes a rectifier configured to rectify an AC signal and supply to the light emitting unit a ripple current signal, and a sequential driving controller configured to generate a reference current, compare the reference current with a channel current from the light emitting unit, and selectively connect one of channel lines connected to respective output terminals of the light emitting devices or array(s) thereof. The sequential driving controller adjusts a level and/or value of the reference current based on the ripple current signal. The reference current is a current flowing between the first node and a ground potential.

主权项

1. A light emitting device driving apparatus configured to control a light emitting unit including light emitting devices or array(s) thereof connected in series, comprising:
a rectifier configured to rectify an AC signal, and supply to the light emitting unit a ripple current signal; a switch driver configured to selectively connect the channel lines and the first node in response to control signals; a current controller connected between the first node and a ground potential, the current controller generating the reference current; a logic controller configured to adjust the level and/or value of the reference current based on a level of the ripple current signal, and generate the control signals; a power supply configured to receive the ripple current signal, and generate an internal voltage and the plurality of selective voltages; and a current adjuster configured to select one of the plural selective voltages, wherein the current adjuster comprises:
an external resistor connection terminal connected to an external resistor,an internal resistor connected at one end to the external resistor connection terminal and another end receiving the internal voltage,an analog-digital converter configured to convert an analog signal to a digital value in response to the setting voltage, wherein the setting voltage is a voltage at the external resistor connection terminal, anda selector configured to select one of the plural selective voltages based on the digital value, and output the selected voltage.