Manually Configuring the PLL

If you want more control over the PLL, you can manually configure it in the PLL Clock Calculator using manual mode. To enable this mode, click the Manual Mode slider to turn it on.

Table 1. PLL Manual Mode Options
Option Choices Description
Pre-Divider (N) 1, 2, 4 The pre-divider value.
Multiplier (M) 1, 2, 4 The multiplier value.
Post-Divider (O) 1, 2, 4, 8, 16, 32, 64, 128 Post-divider value.
CLK Divider n 2 - 128 Clock divider for each output.
Phase Shift Value n 0 - 7 Post-divider VCO cycle delay to phase shift, in degrees:
0: No phase shift
1: 0.5
2: 1
3: 1.5
4: 2
5: 2.5
6: 3
7: 3.5

The post-divider VCO cycle delay relates to the phase shift as shown in the following equation:

Phase shift (in degrees) = ( (Post-divider VCO cycle delay x O x FCLKOUT) / FVCO ) x 360

where:
  • O is the post-VCO division ration
  • FCLKOUT is the output frequency
  • FVCO is the VCO frequency