Other Parts Discussed in Thread: UCC27201A-Q1
Hi Expert,
For high power 48V BLDC driver(about 500W or more) design (usually for Robotics appliation). Because it's non-isolation design, we often face a dilemma that we need to keep a complete ground plane or separate the signal ground (GND) from inverter power ground (PGND). GND and PGND need to be connected together finally because of non-isolation design.
The traditional saying is that GND and PGND need to be separated, then single connection in power input, which can isolate the noise from high power PGND to GND because of PGND is large current. But there are still some signal interconnections between GND and PGND, such as gate driver siganls, current sample signals. They need to cross between two separate planes
so how about keeping a complete ground plane for both GND and PGND? In motor driver design, usually there are several ground planes for large current. Keeping a complete ground plane means a lowest impedance plane for all components. Also it will be a good path for thermal conduction. The PCB layout will be much simpler. Inverter related power components will be kept in same area.
What's the best practice for control ground (GND) and inverter PGND in non-isolation motor driver PCB design?
Thanks
Peter