According to the low-
capacitance transient suppression protection device provided by the embodiment of the invention, the highly-doped substrate and the double-layer
epitaxy are adopted, the high-resistance substrate is adopted as a
common collector, and two NPN triodes with floating base regions are connected in series, so that the
capacitance can be halved through the series design. And meanwhile, an SCR structure with ultralow trigger
voltage is connected in parallel, and the problem that the device cannot be normally and independently applied due to the one-way
cut-off characteristic of a high-resistance substrate
triode is solved by utilizing the punch-through characteristic of a
semiconductor. On the whole, according to the structure, the
capacitance of the device is halved through the two NPN structures connected in series, so that smaller capacitance is obtained, then the low-capacitance TVS is formed through the ultra-low trigger
voltage SCR structures connected in parallel, and the special requirements of customers for the protection device in practical application are met.