A double-buffered DAC, on the other hand, may be loaded with parallel data, serial data, or with 4-bit or 8-bit words, and the output will be unaffected until the new data is completely loaded and the DAC receives its update instruction. The other convenience of the double-buffered structure is that many DACs may be updated simultaneously. Data is loaded into the first rank of each DAC in turn, and when all is ready, the output buffers of all DACs are updated at once. There are many DAC applications where the output of several DACs must change simultaneously, and the double-buffered structure allows this to be done very easily.