An LED array switching apparatus, comprising: a plurality of LED arrays (D1 to Dn) arranged in a serial path, each LED array having a forward voltage; a voltage supply coupled to the plurality of LED arrays; a plurality of current sources (Gl to Gn) selectively coupled to the LED arrays, each of the current sources being configured to switch between a current regulating state and an open state; and a controller that is configured to perform at least one voltage comparison of a voltage of the voltage supply with at least one reference voltage (Vref) and outputs at least one control signal (CS1 to CSn) generated based on at least one of: (a) said at least one comparison, and (b) currents through one or more of the current sources, the control signals controlling the turning on and off of at least one switch and a current source associated with the at least one switch, wherein when the at least one switch is turned off the current source is in an open state, the controller, the at least one switch and the plurality of current sources cooperating together such that: when the voltage of the voltage source is below the at least one reference voltage, and/or when a predetermined level of current passes through the one or more current sources, said at least one switch is closed and one or more associated current sources of said plurality of current sources are controlled so as to break the serial path into one or more parallel paths each including less than all of the LED arrays; characterised in that the LED array switching apparatus is configured to turn on in sequence from a first array of said LED arrays to a last array of said LED arrays when the voltage of the voltage supply is increasing and reverse the sequence when the voltage of the voltage supply is decreasing. a plurality of LED arrays (D1 to Dn) arranged in a serial path, each LED array having a forward voltage; a voltage supply coupled to the plurality of LED arrays; a plurality of current sources (Gl to Gn) selectively coupled to the LED arrays, each of the current sources being configured to switch between a current regulating state and an open state; and a controller that is configured to perform at least one voltage comparison of a voltage of the voltage supply with at least one reference voltage (Vref) and outputs at least one control signal (CS1 to CSn) generated based on at least one of: (a) said at least one comparison, and (b) currents through one or more of the current sources, the control signals controlling the turning on and off of at least one switch and a current source associated with the at least one switch, wherein when the at least one switch is turned off the current source is in an open state, the controller, the at least one switch and the plurality of current sources cooperating together such that: when the voltage of the voltage source is below the at least one reference voltage, and/or when a predetermined level of current passes through the one or more current sources, said at least one switch is closed and one or more associated current sources of said plurality of current sources are controlled so as to break the serial path into one or more parallel paths each including less than all of the LED arrays; characterised in that the LED array switching apparatus is configured to turn on in sequence from a first array of said LED arrays to a last array of said LED arrays when the voltage of the voltage supply is increasing and reverse the sequence when the voltage of the voltage supply is decreasing. when the voltage of the voltage source is below the at least one reference voltage, and/or when a predetermined level of current passes through the one or more current sources, said at least one switch is closed and one or more associated current sources of said plurality of current sources are controlled so as to break the serial path into one or more parallel paths each including less than all of the LED arrays; characterised in that the LED array switching apparatus is configured to turn on in sequence from a first array of said LED arrays to a last array of said LED arrays when the voltage of the voltage supply is increasing and reverse the sequence when the voltage of the voltage supply is decreasing.