Molten drop liquid bridge detection circuit in welding

A molten drop liquid bridge detection circuit in welding comprises a voltage feedback processing module, a synchronous sampling signal processing module, a sampling holding module and a voltage difference value comparison module. The voltage feedback processing module is used for filtering and scaling down the output signal of the welding machine and sending the processed output signal of the welding machine to the sampling and holding module; the synchronous sampling signal processing module generates a synchronous signal and a delay sampling signal according to the positive and negative conduction signals, and sends the synchronous signal and the delay sampling signal to the sampling holding module; the sampling and holding module is used for sampling a signal output by the voltage feedback processing module according to the delay sampling signal, storing two adjacent sampling signals at the same state moment of the main transformer in real time according to a synchronizing signal and sending the two adjace