I would suggest that you check out stats from historical playoff series to be sure, but I don't think it has ever happened.
There are 82 games in a regular NHL season. (not counting playoff games)
Every series in the NHL playoffs is a best of 7
if you win the championship playoff series in the NHL
New YorkIslanders from 1990 to 1984
All NHL Playoff series are best of 7, meaning if you lose 4 you are out
When one the final two playoff teams wins the best of 7 series.
Brodeur in 03 had 3 against the ducks
The NHL playoff schedule works similarly every year. There are sixteen teams that make the playoffs and these face off in best of seven series until only eight teams remain.
The Toronto Maple Leafs came back and beat the Detroit Red Wings in the 1942 Stanley Cup final. The New York Islanders, in only their third NHL season, came back against the Pittsburgh Penguins in the quarter-finals in 1975. And in 2010, the Philadelphia Flyers came back from 3-0 in the series as well as 3-0 in Game 7 to take the Eastern Conference semifinal against the Boston Bruins
there is 7 games, but its best of seven so it could be over after 4 games