A car valeter stopped by gardai immediately told them "I've been drinking and driving, arrest me", a court heard.
Eric Fowler (34) had been at a function at his sister's house but foolishly drove home after a short sleep.
Judge David McHugh fined him €500 and disqualified him from driving for two years.
The defendant, of Blakestown Cottages, Dublin 15, admitted drink-driving when he appeared before Blanchardstown District Court.
Garda Tara Byrne said gardai were on mobile patrol on Church Road, Mulhuddart, on April 22 when they saw a black VW Golf driving at speed toward Mulhuddart village.
Gardai followed the car, which was driving erratically in and out of the white line.
Gda Byrne said Fowler was stopped in Blakestown Road and immediately admitted to the garda he had been drink-driving.
Fowler was later breathalysed and produced a reading of 60mg of alcohol per 100ml of breath.
Fowler's defence lawyer said he employed two staff.
He made a grave error of judgment and a driving ban would have a serious impact on him.