Lpc2000

Hello,

has someone used the LPC2106 with a oscillator frequency of 2,5 MHz or 5
MHz?
According to data sheet it should be between 10 and 25 MHz.
It needn't to be fully stable (a few minutes to hour is enough), because it
is only for a short measurement task. Internally i still want to use the PLL
with M = 11 and P = 4 to get a internal frequency of 27,5 MHz or 55 MHz.

Is the PLL still running at such low frequencies ? Are there any known side
effect, that core or peripheral is not working anymore ?

Regards,

         Martin