Voltage converter and lighting apparatus incorporating a voltage converter

A method of operating a lighting apparatus, the lighting apparatus comprising a voltage converter operable to generate an output voltage based at least partially on a voltage control signal received by the voltage converter, the voltage control signal being high for one or more time slots and low for one or more time slots within each of a plurality of timing blocks within a fine control period, the method comprising:

• setting a duty cycle of the voltage control signal to a first value for one or more first timing blocks of the fine control period, wherein the voltage control signal is high for a first number of time slots within each of the first timing blocks;
• and
• setting the duty cycle of the voltage control signal to a second value for one or more second timing blocks of the fine control period, wherein the voltage control signal is high for a second number of time slots within each of the second timing blocks, the second number being different than the first number;
• wherein the first number of time slots within each of the first timing blocks and the second number of timing slots within each of the second timing blocks have similar relative magnitudes, whereby the duty cycle across the fine control period has an average value between the first and second values to provide an increased resolution to control the output voltage from the voltage converter.

A lighting apparatus comprising:

• a voltage converter operable to generate an output voltage defined between a high voltage rail and a low voltage rail coupled to the output of the voltage converter, the output voltage based at least partially on a voltage control signal received by the voltage converter, the voltage control signal being high for one or more time slots and low for one or more time slots within each of a plurality of timing blocks within a fine control period;
• at least one first LED channel coupled between the high voltage rail and the low voltage rail, the at least one first LED channel comprising one or more LEDs coupled in series;
• and
• a control module operable to:
• set a duty cycle of the voltage control signal to a first value for one or more first timing blocks of the fine control period, wherein the voltage control signal is high for a first number of time slots within each of the first timing blocks;
• and
• set the duty cycle of the voltage control signal to a second value for one or more second timing blocks of the fine control period, wherein the voltage control signal is high for a second number of time slots within each of the second timing blocks, the second number being different than the first number;
• wherein the first number of time slots within each of the first timing blocks and the second number of timing slots within each of the second timing blocks have similar relative magnitudes, whereby the duty cycle across the fine control period has an average value between the first and second values to provide an increased resolution to control the output voltage from the voltage converter.

A control apparatus operable to control a lighting apparatus, the lighting apparatus comprising a voltage converter operable to generate an output voltage based at least partially on a voltage control signal received by the voltage converter, the voltage control signal being high for one or more time slots and low for one or more time slots within each of a plurality of timing blocks within a fine control period,

• wherein the control apparatus is operable:
• to set a duty cycle of the voltage control signal to a first value for one or more first timing blocks of the fine control period, wherein the voltage control signal is high for a first number of time slots within each of the first timing blocks;
• and
• to set the duty cycle of the voltage control signal to a second value for one or more second timing blocks of the fine control period, wherein the voltage control signal is high for a second number of time slots within each of the second timing blocks, the second number being different than the first number;
• wherein the first number of time slots within each of the first timing blocks and the second number of timing slots within each of the second timing blocks have similar relative magnitudes, whereby the duty cycle across the fine control period has an average value between the first and second values to provide an increased resolution to control the output voltage from the voltage converter.