Research On 150A Transmission Line Pulse (TLP)

As apower switch,VDMOS devices withhigh switching speed,high voltage,lowresistance,wide safety working area,good thermal stability and so on.VDMOS devices play an important role in the application of power electronics.However,the problem is that the power VDMOS device with special internal structure,static or related voltage transients and other external environment is very easy to form the latch-up,resulting in circuit failure,or even burn the chip.A large number of researchshows that many of the power IC on-site failures are caused by the latch-up effect of over-stress failure,which seriously hampered China’s civilian and military electronic equipment reliability.At present,the research on the latch-up effect of power devices has been difficult to carry out.The fundamental reason lies in the lack of testing means.150 A Transmission Line Pulse(TLP)is a new research direction for indirectly testing the electrical latch-up effect of power devices.It can produce less heat before high pressure failure,to achieve "cold trigger",thentest VDMOS and other power devices to withstand the pulse of the maximum off-state breakdown latch trigger current and other parameters.It determines the anti-latching device protection technology effective,while saving development costs.Given the above issue,the 150 A Transmission Line Pulse has been developed for the above problems.Details as follows:(1)Further study on the mechanism and characteristics of the TLP test system and 150 A TLP test system.The hardware implementation method of 150 A TLP test system is presented.A low impedance transmission line is developed and the pressure value of terminal polarizer,relays and so on is improved.To solve the problem of system overshoot or oscillation,advanced high power filter structure is proposed.Using relay mode of secondary drive,the 150 A TLP test automatic system is achieved.(2)Using the 150 A TLP testing system,the detection of the switching time and the calibration of the charging voltage are completed.The output waveform of the system is obtained,and the parameters of the system are verified,which created favorable conditions for the following program.(3)According to the analysis of test system for customized software requirements,design the system function module and flow chart,with the help of LabVIEW graphical programming software were completed,driving on the bottom and top middle function user interface program design and realize automatic operation of 150 A TLP test system.(4)Application experiments of the 150 A TLP automated test system show that the system is stable,and the test error is small.It can accurately test the device latch-up current,evaluate the anti-latch performance of the device.Through the high reliability chip anti-latch ability assessment device,effectively measure the anti-latching ability of different products.The 150 A TLP can also be used to test the impact of different gate voltage on the performance of power devices,which provides a means of reliability test for ultra-fast high-power VDMOS devices and guarantees further studies of the latch-up performance of high power devices.