KEY GENERATION DEVICE, ENCODING/DECODING DEVICE, AND KEY GENERATION METHOD

摘要

A key generation device for generating a key whose value cannot be known easily by a circuit designer or the lie, thereby protecting the key security. Random number generation circuits (51, 52, 53, ...) generate random numbers by different clocks (CLK1, CLK2, CLK3, ...). A calculation circuit (59) calculates the random numbers output from the random number generation circuits (51, 52, 53, ...) so as to obtain an N-bit random number (RA) as an output of a random number generation unit (50). This random number (RA) is extracted via a key selector (43). A key register (45) is latched by an acquisition enable signal (EN) from a timing monitoring counter (47) driven by a clock (CLKA) which is different from the clocks (CLK1, CLK2, CLK3, ...), thereby obtaining a hardware key which is a unique secret key.