What's the difference between the two? Do you need a special digital VHF radio to receive D-ATIS broadcasts?
Digital ATIS is an enhancement of the Tower Data Link Service (TDLS) and uses the Pre-Departure Clearance (PDC) System microcomputer to automate the delivery of airport and terminal area operational and meteorological information to aircraft flightcrews. Two phases of development are planned. The first phase will provide, via data link, a digital version of the ATIS /4 to flightcrews. Voice recording will continue to be utilized in the preparation of the ATIS broadcast. The second phase will add automated voice generation for the ATIS broadcasts.
Its part of a larger data link system that allows aircrafts and controllers to communicate certain things (weather info, clearances etc) with out clogging the radio channel.
Some ATIS systems now have a voice synthesizer reading out the reports so that no one needs to manually update the recording every hour.