
RM0453 Rev 2
633/1454
RM0453
True random number generator (RNG)
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22
True random number generator (RNG)
22.1 Introduction
The RNG is a true random number generator that provides full entropy outputs to the
application as 32-bit samples. It is composed of a live entropy source (analog) and an
internal conditioning component.
The RNG is a NIST SP 800-90B compliant entropy source that can be used to construct a
non-deterministic random bit generator (NDRBG).
The RNG true random number generator has been pre-certified NIST SP800-90B. It has
also been tested using German BSI statistical tests of AIS-31 (T0 to T8).
22.2
RNG main features
•
The RNG delivers 32-bit true random numbers, produced by an analog entropy source
conditioned by a NIST SP800-90B approved conditioning stage.
•
It can be used as entropy source to construct a non-deterministic random bit generator
(NDRBG).
•
It produces four 32-bit random samples every 412 AHB clock cycles if f
AHB
< 77 MHz
(256 RNG clock cycles otherwise).
•
It embeds start-up and NIST SP800-90B approved continuous health tests (repetition
count and adaptive proportion tests), associated with specific error management
•
It can be disabled to reduce power consumption, or enabled with an automatic low
power mode (default configuration).
•
It has an AMBA AHB slave peripheral, accessible through 32-bit word single accesses
only (else an AHB bus error is generated, and the write accesses are ignored).