For the millimeter voltage signal communication equipment in high-definition cameras, automatic control, and microelectronics technology, due to the built-in extremely sensitive MCU, digital integrated chips, and other sensitive components, the signal protection circuit of traditional discharge tubes with voltage limiting components cannot solve the instantaneous pulse exceeding 200V when the discharge tube starts (which must be observed using an oscilloscope with a sampling rate of over 100MHz/1GS/S). This pulse is the main reason for destroying sensitive digital integrated circuits, and there is no effective solution in the industry to solve this problem in the past. The Oushen ultra-low voltage signal surge protector has completely overcome this problem through Oushen's patented technology. The output residual voltage is less than 5V under 10kA (8/20 μ s) or 2.5kA (10/350 μ s) impulse current, and the working bandwidth can reach 1GHz. The maximum discharge current can reach 2.5kA (10/350 μ s) required by D1 testing, which can be used for field lightning protection requirements from LPZO to LPZ1 zone.