| 摘要 |
PURPOSE: A circuit for protecting a program data is provided to prevent code data signals stored to the inside of a program memory from being easily accessed from an outer source regardless of that the entire area of a program memory array is coded, and selectively output a code data being in the inside of the program memory array, in which an address is located, to an outer port. CONSTITUTION: The circuit includes an address scrambling portion(60) and a scramble control portion(50) in a semiconductor device which is composed of a word line decoder(1), a bit line decoder(2) and a program memory array(3) and of which an enabling signal for reading is inputted to the word line decoder and bit line decoder. The address scrambling portion changes the positions of an address signal inputted to the word line decoder and an address signal inputted to the bit line decoder. The scramble control portion controls the address scrambling portion according to a protection enabling signal being inputted.
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