Portable data carrier provided with access protection by dividing up codes

The invention relates to a protection a semiconductor chip data storage medium method of secret data, wherein the semiconductor chip at least comprises a memory with a travelling program memory, wherein the travelling program comprises multiple instructions, thereby each of the through is connected with the semiconductor chip external detection to the signal obtaining. An objective of the present invention is used is fixed to the differential energy the groove (DPA) or wire protection DPA the secret data in data base a chip. The aspect parts; the invention provides, for realizing safe operation and semiconductor chip, the data secret decomposed is at least three part, wherein the secret data latching to the data carrier or a data type substrate, and calculates random number and is the number of the mode unit, from the first data part of the adjacent up to perform, the second part of the complement of division operation, and third portion is a random the automatic.