RE: [CAD_CAM_EDM_DRO] Chopper max voltage?

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>From: Chris Hellyar [mailto:chris@...]
>... Also the heatsink is
>mechanically mounted to the PCB with alloys spacers to reduce mechanical
>stress on the driver legs etc.

Although this may reduce the stress caused by vibration (i.e. it steadies that
huge resonant springy mass hanging off those poor little terminals), it can also
*cause* stress as the heat sink and the device's leads undergo differential
thermal expansion. I suspect that the latter stresses, which would typically be
relieved through flexing of the PCB, easily exceed the stresses caused by
vibration and the weight of the heat sink.
-Kevin Martin