LM25117: LM25117 producing half the fsw frequency than the RT resistor value should give.

Hi There,

We have a default LM25117 switcher circuit with 24V I/p, 12V/12A output requirement, but have the following issue:-

Although we have selected Rt as 12K1 (should produce about 400KHz fsw), we are getting half that, i.e. 200KHz.

Could you advise as to what would cause this?

Thanks.