The need for security in industries such as communication, computerized payment systems, and disk encryption has resulted in the widespread use of cryptographic technologies. Random numbers are used in a variety of cryptographic applications, ranging from key generation and encryption to masking protocols and online gambling, to improve and protect the privacy of electronic communications. Predictable random numbers are a significant flaw in cryptography systems that generate secret keys. TRNGs (true random number generators) are required for the operation of many different cryptographic systems. These are used to generate PINs and passwords, authentication tools, keys, random padding, and nonces. Electrical noise, a type of randomness in electronics, is mostly to blame for the failure. Most of these security measures can be implemented in hardware using field-programmable gate arrays (FPGAs). The TRNG recommended for Xilinx-FPGA applications is based on the pulse frequency detection method.