Other Parts Discussed in Thread: LM5104,
Hello,
When using two TPS2834 MOSFET drivers (and MOSFETS) in a full bridge configuration (as seen in the schematic below) and in synchronous mode (by holding the SYNC pin high), the low side driver signal LOWDR (going into the gate of the low side MOSFET) would remain low instead of switching inversely to the HIGHDR signal, this resulted in the system connected on the output not operating at all. Other sections of the design that use the MOSFET driver in half bridge configuration work without any issues. The same full bridge configuration was tested with the LM5104 MOSFET driver and works without any issue or need for modification. It is however not possible for me to use LM5104 MOSFET for this design.
In order to get the TPS2834 MOSFET drivers working in the configuration shown in the schematics, a resistor was connected across the drain and source of both the low side MOSFETs used. The LOWDR signal (going into the gate of low side MOSFET) was then seen operating inversely to the HIGHDR.
Whilst the MOSFET drivers were seen working with the modification, I am not keen on proceeding with the design, I would much prefer if it was working without this modification and would like your feedback in order to help me resolve this issue.
In the simulation that I found online I noticed that the dead time pin was pulled to ground instead of connected to the bridge of the two MOSFETS, I have yet to test this however I do not think it will resolve the issue.
in the schematics attached:
VCC = 12V DC
EX1-A and EX1-B are PWM signals that are the inverse of each other.
If you have any questions then please let me know.
Thanks