Catalysis of the ATP-dependent activation of D-alanine and its transfer as a thiol ester to the phosphopantheinyl prosthetic group of a D-alanyl carrier protein, according to the reaction: ATP + D-alanine + a  = a D-alanyl- + AMP + diphosphate.
D-alanine:poly(phosphoribitol) ligase (AMP-forming)