An LED driver (20, 30, 40, 50, 90A) for generating an output power for driving at least one LED from an input power, provided by a power source originally designed for powering a high-intensity discharge lamp, the LED driver (20, 30, 40, 50, 90A) comprising: an input arrangement (21, 91) adapted to receive the input power from the power source; an output arrangement (22, 52, 92) adapted to provide the output power for driving the at least one LED; first circuitry (23, 33, 43, 53, 93) defining a first current path between the input arrangement (21, 91) and the output arrangement (22, 52, 92), the first circuitry (23, 33, 43, 53, 93) comprising a first rectifying arrangement (D1, D2) arranged to connect the input arrangement (21, 91) to the output arrangement; second circuitry (24, 34, 44, 54, 64, 94) defining a second, different current path between the input arrangement (21, 91) and the output arrangement (22, 52, 92), the second circuitry (24, 34, 44, 54, 64, 94) comprising a second rectifying arrangement (D7, D8) and modifying circuitry (Lpfc, Mpfc, D5) arranged to connect the input arrangement (21, 91) to the output arrangement (22, 52, 92); a power source type determiner adapted to detect an occurrence of a pulse in a voltage level of the input power and adapted to determine if the power source is of: a first type, in which the power source comprises a functional ignitor circuit able to ignite a high-intensity discharge lamp, if the pulse has a length less than a predetermined length and a magnitude of more than a predetermined magnitude; or a second type, in which the power source comprises no functional ignitor circuits able to ignite a high-intensity discharge lamp, a controller adapted to: direct the current of the input power down the first current path in response to the power source type determiner determining that the power source is of the first type; and direct the current of the input power down the second current path in response to the power source type determiner determining that the power source is of the second type. an input arrangement (21, 91) adapted to receive the input power from the power source; an output arrangement (22, 52, 92) adapted to provide the output power for driving the at least one LED; first circuitry (23, 33, 43, 53, 93) defining a first current path between the input arrangement (21, 91) and the output arrangement (22, 52, 92), the first circuitry (23, 33, 43, 53, 93) comprising a first rectifying arrangement (D1, D2) arranged to connect the input arrangement (21, 91) to the output arrangement; second circuitry (24, 34, 44, 54, 64, 94) defining a second, different current path between the input arrangement (21, 91) and the output arrangement (22, 52, 92), the second circuitry (24, 34, 44, 54, 64, 94) comprising a second rectifying arrangement (D7, D8) and modifying circuitry (Lpfc, Mpfc, D5) arranged to connect the input arrangement (21, 91) to the output arrangement (22, 52, 92); a power source type determiner adapted to detect an occurrence of a pulse in a voltage level of the input power and adapted to determine if the power source is of: a first type, in which the power source comprises a functional ignitor circuit able to ignite a high-intensity discharge lamp, if the pulse has a length less than a predetermined length and a magnitude of more than a predetermined magnitude; or a second type, in which the power source comprises no functional ignitor circuits able to ignite a high-intensity discharge lamp, a first type, in which the power source comprises a functional ignitor circuit able to ignite a high-intensity discharge lamp, if the pulse has a length less than a predetermined length and a magnitude of more than a predetermined magnitude; or a second type, in which the power source comprises no functional ignitor circuits able to ignite a high-intensity discharge lamp, a controller adapted to: direct the current of the input power down the first current path in response to the power source type determiner determining that the power source is of the first type; and direct the current of the input power down the second current path in response to the power source type determiner determining that the power source is of the second type. direct the current of the input power down the first current path in response to the power source type determiner determining that the power source is of the first type; and direct the current of the input power down the second current path in response to the power source type determiner determining that the power source is of the second type.