Circuit Simulation And Experiments On Electromagnetic Compatibility Of Semiconductor Bridge Initiator

In order to select the appropriate protective device for the electromagnetic protection of semiconductor bridge initiators,the circuit simulation with PSpice was introduced in SCB electromagnetic research.Different device were discussed and compared in this paper.The main conclusions are as follows:(1)A SCB electrical model was built and applied in the simulation of capacitor discharge and electrostatic discharge.When the discharge voltage was high enough to fire the bridge,the first peak in the simulation curve coincide with that in the experimental curve;There is deviation between the second peaks which would not impact the analysis.When at low voltage,the complete feature curve could not appear during 15?s.(2)When SMBJ6.0CA was used as a protective device,SCB could not be fired at 22?F 16V discharge.When SMBJ8.0CA was used,SCB was fired,but the firing time is a little delayed.When SMBJ12CA or SMBJ15CA was used,the firing process was not effected.(3)The electrostatic discharging simulation result show that SCB could pass the test demanded in Chinese military standards,but not pass the test in US military standard.A 500pF capacitor and a 50O2 resistor employed in the electrostatic discharge circuit.the critical damage voltage of SCB was between 11KV and 18KV.SCB under the protection of SMBJ8.OCA could withstand the 50KV static electricity.And SCB under the protection of SMBJ12CA could withstand the 40KV static electricity.(4)Through experiments we found the critical damage voltage of SCB with no protection was at 13KV.And SCB under protection of SMBJ8.0CA or SMBJ12CA could withstand the 30KV static electricity.(5)Wave with different forms would be weakened when a capacitor was connect with SCB in parallel.The capacitor with large capacitance could dedcline more current.A TVS device could play a role of RF protection for its junction capacitor;however an extra resistance would emerge when a TVS device was in a RF protecting circuit.