HobbyWing EZRun 80A Review - RC-Monster Forums

himalaya · 03.05.2009, 01:21 AM

The 150A uses 36 MOSFETs, ON semi's NTMFS4833N(the MMM uses NTMFS4108N).
Here's my picture.
On the top side of PCB: 4x6 = 24 FETs，there are two more rows underneath the power PCB, 2x6 = 12 FETs. Note the way the heatsink touches. Looks like HobbyWing was trying to cool the PCB, not directly the FETs (to take care of the ones on back side maybe? ).

jzemaxx · 03.05.2009, 01:28 AM

Quote:

Originally Posted by himalaya

The 150A uses 36 MOSFETs, ON semi's NTMFS4833N(the MMM uses NTMFS4108N).
Here's my picture.
On the top side of PCB: 4x6 = 24 FETs，there are two more rows underneath the power PCB, 2x6 = 12 FETs. Note the way the heatsink touches. Looks like HobbyWing was trying to cool the PCB, not directly the FETs (to take care of the ones on back side maybe? ).

Very nice......matches the MMM.

BrianG · 03.05.2009, 10:42 AM

Quote:

Originally Posted by himalaya

The 150A uses 36 MOSFETs, ON semi's NTMFS4833N(the MMM uses NTMFS4108N).
Here's my picture.
On the top side of PCB: 4x6 = 24 FETs，there are two more rows underneath the power PCB, 2x6 = 12 FETs. Note the way the heatsink touches. Looks like HobbyWing was trying to cool the PCB, not directly the FETs (to take care of the ones on back side maybe? ).

Now that makes more sense. 36 of those FETs more than meets the 150A spec. Those metal bars attached to the PCB is a good idea IMO because the PCB carries the majority of the heat (heat doesn't travel as well through the plastic FET casing as it does through the leads).

himalaya · 03.06.2009, 07:25 AM

Quote:

Originally Posted by BrianG

Now that makes more sense. 36 of those FETs more than meets the 150A spec. Those metal bars attached to the PCB is a good idea IMO because the PCB carries the majority of the heat (heat doesn't travel as well through the plastic FET casing as it does through the leads).

Yes, the metal bars act as a heat transfer, as well as a current flew path, a smart design.