13.9.6.4.2.4 Accuracy

There are three main factors that determine the accuracy of F_clkdfll48m. These can be tuned to obtain maximum accuracy when fine lock is achieved.

• Fine resolution. The frequency step between two Fine values. This is relatively smaller for higher output frequencies.
• Resolution of the measurement: If the resolution of the measured F_clkdfll48m is low, i.e., the ratio between the CLK_DFLL48M frequency and the CLK_DFLL48M_REF frequency is small, the DFLL48M might lock at a frequency that is lower than the targeted frequency. It is recommended to use a reference clock frequency of 32KHz or lower to avoid this issue for low target frequencies.
• The accuracy of the reference clock.