RoadTest: Infineon Gate Driver with Truly Differential Input
Author: BikeViolin
Creation date:
Evaluation Type: Development Boards & Tools
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: Closest Comparison is other Low Side Gate Driver ICs but these do not have the advantages of the Truly Differential Input.
What were the biggest problems encountered?:
Detailed Review:
The performance of the Differential Gate Driver in an open loop configuration well exceeded my expectations. As my measurements show, there is practically no change in Output Voltage, Inductor current or Bridge Voltage for a wide range of DC Ground Shifts. The change that does occur is significantly less than the accuracy of the measurement system.
Infineon's application note describes it rather well, the first section is "recommended reading" for this review:
I hand made some little coils of wire to insert into the LeCroy Oscilloscope Probe connectors to allow my Rigol probes to be used for making measurements, these were wrapped in insulating tape to prevent the probe tip shorting to the shield of the connector and installed as a snug fit inside the connector.
I attached two 47 ohm high power resistors to heatsinks using thermally conductive epoxy and used these resistors as dummy loads for the evaluation board. I used a 4 channel oscilloscope with 2 passive voltage probes on X2 (AC GND Shift) and X7 (Bridge Output), a current clamp probe to measure AC inductor current and a differential probe to measure DC Ground Shift. I also used a multimeter to measure the DC voltage output of the evaluation board.
I used a spreadsheet to list the position of the potentiometer, approximate output load, and the output voltage whilst recording the oscilloscope's automated measurements with screenshots saved to a memory stick, I noted in the spreadsheet the number of the image file for each setup. Once I had finished the list of setups, I added the automated measurements into the spreadsheet from the images.