LED driving system and LED driving circuit

The invention discloses an LED driving system and an LED driving circuit. The LED driving system comprises a first LED driving circuit and a second LED driving circuit, and each of the first LED driving circuit and the second LED driving circuit comprises a first state detection circuit, a second state detection circuit and a first feedback control circuit. The first state detection circuit is coupled to a plurality of LED lamp strings to receive a plurality of clearance detection voltages and generate at least one first state signal. The second state detection circuit receives a downstream feedback signal and generates at least one second state signal. The first feedback control circuit generates a first feedback control signal based on the at least one first state signal and the at least one second state signal. The second state detection circuit of the first LED drive circuit is coupled to the first feedback control circuit of the second LED drive circuit to receive a first feedback control signal generate