Probing for GaN Half Bridge
New GaN power transistors enable design engineers to operate their designs at very high switching frequencies – up to 10 times the traditional switching frequencies of designs based upon silicon MOSFET transistors. When evaluating these high speed designs, the use of proper voltage measurement techniques is very critical in order to obtain consistent results.
As an example, the following measurements were performed on pulses at the mid-point of VisIC’s GaN Half Bridge application board. When the oscilloscope probe tool was not compatible it caused ringing and affected the shape of the voltage waveform.
To obtain the correct measurements in VisIC’s lab we used the BumbleBee Differential HV oscilloscope probe, the improper measurements were measured with a PHVS 1000-RO High Voltage Passive oscilloscope probe, which has been a typical probe used by power conversion designers.