Patent ID: 9554433
Date: 2017-01-24
CPC Classifications: G09G,H05B

Claim:
1. A driver system for driving a plurality of LED's, the driver system comprising: a control module having an input for receiving operating data; and at least two driver modules, each driver module for driving at least one of the LED's, each of the driver modules comprising: a hysteretical converter for generating an LED current to power the LED's, and a controller electrically connected to the hysteretical converter for controlling the hysteretical converter, wherein each of the driver modules comprises a respective reference signal generator for generating a respective reference signal, the reference signal generator being connected to a setpoint input of the hysteretical convertor to provide the respective reference signal to the setpoint input of the hysteretical convertor, causing each driver module to generate, by its respective hysteretical convertor its own LED current proportional to the respective reference signal, wherein each of the driver modules receives the same supply voltage, and further wherein the controller of each of the driver modules is configured to measure a value of the supply voltage thereby using the reference signal provided by the reference signal generator of the respective driver module as a reference, and thereby comparing by each driver module the supply voltage with the reference signal of the reference signal generator of that respective driver module, control module being configured to calibrate the LED currents of the driver modules in respect of each other by comparing the measurements of the value of the supply voltage of the at least two driver modules with each other and calibrating the reference signal generators of the at least two driver modules in respect of each other based on a difference between the measurements of the value of the supply voltages by the driver modules, whereby each driver module measures the same supply voltage using its own reference signal generator as its respective reference.