SNOSD91B March 2019 – February 2020
PRODUCTION DATA.
The circuit used to measure most switching parameters is shown in Figure 13. The top LMG341xR150 in this circuit is used to re-circulate the inductor current and functions in third-quadrant mode only. The bottom device is the active device; it is turned on to increase the inductor current to the desired test current. The bottom device is then turned off and on to create switching waveforms at a specific inductor current. Both the drain current (at the source) and the drain-source voltage is measured. The specific timing measurement is shown in Figure 14. It is recommended to use the half-bridge as double pulse tester. Excessive 3rd quadrant operation may over heat the top LMG341xR150.
Figure 13. Circuit Used to Determine Switching Parameters
Figure 14. Measurement to Determine Propagation Delays and Slew Rates