600V 71A — what the rating means for the power stage
The 600 V reverse voltage rating suits it for 400 VDC bus rails in power supplies and motor drives with adequate derating margin; the 71 A forward current rating defines the conduction path for high-current rectification or freewheeling stages.
Package and thermal path
The tab carries the cathode current and provides the primary heat path — the PCB copper area under the tab sets the junction-to-ambient thermal resistance. The two-lead-plus-tab configuration means the tab is not a separate signal pin; the layout must connect it to the cathode net with sufficient copper pour.