Hi @bobpaddock ,
TRNG is based on collecting bits from a random noise source. This random noise source is a ring oscillator that is sensitive to random noise (temperature variations, voltage variations, cross-talk and other random noise) within the device in which the TRNG is used. TRNG can be used to seed a hardware or software based implementation of a DRBG defined by SP800-90.
TRNG hasn't been certified with FIPS and there are no plans to do it for KINETIS.
But, the TRNG is designed in accordance with SP800-90B guidelines, if you combine it with a SW DRBG (per SP800-90B guidelines), it should meet the FIPS requirements.
Regards,
Jing