Led lighting circuit and led luminaire comprising the same

A LED lighting circuit comprising:

• an LED arrangement comprising a first LED string, with a first tap between two LEDs in the first LED string, and a second LED string, with a second tap between two LEDs in the second string, the first and second LED strings connected in parallel;
• a power supply arrangement adapted to receive an input power and to provide an output power to the LED arrangement;
• a bidirectional conduction arrangement connected between the first tap and the second tap and adapted to be triggered to be conductive when
• either a voltage potential difference between the first tap and the second tap exceeds a threshold in case that the first LED string and the second LED string are nominally identical and the first and second taps are at the same relative position in respective string, or
• a change in a voltage potential across the first LED string and the second LED string is sensed,
• wherein the bidirectional conduction arrangement is adapted to generate a fault signal at a first direction output upon a current conducted by the bidirectional conduction arrangement;
• and
• a control circuit connected to the first detection output and adapted to control the power supply arrangement to decrease the output power when receiving said fault signal.