SI5338 Datasheet, PDF (21/170 Pages) Silicon Laboratories – I2C-PROGRAMMABLE ANY-FREQUENCY, ANY-OUTPUT QUAD CLOCK GENERATOR

Si5338
Disable Outputs
Set OEB_ALL = 1; reg230[4]
Register
Map
Use ClockBuilder
Desktop v2.7 or later
Input clocks are
validated with the
LOS alarms. See
Register 218 to
determine which LOS
should be monitored
Pause LOL
Set DIS_LOL = 1; reg241[7]
Write new configuration to device
accounting for the write-allowed mask
(See Section 6.1)
Validate input clock status
NO
Is input clock valid?
YES
Configure PLL for locking
Set FCAL_OVRD_EN = 0; reg49[7]
Initiate Locking of PLL
Set SOFT_RESET = 1; reg246[1]
Restart LOL
Set DIS_LOL = 0; reg241[7]
Wait 25 ms
Confirm PLL lock status
PLL is locked when
PLL_LOL, SYS_CAL, and
all other alarms are
cleared
NO
Is PLL locked?
YES
Copy FCAL values to
active registers
Copy registers as follows:
237[1:0] to 47[1:0]
236[7:0] to 46[7:0]
235[7:0] to 45[7:0]
Set 47[7:2] = 000101b
Set PLL to use FCAL values
Set FCAL_OVRD_EN = 1; reg49[7]
Enable Outputs
Set OEB_ALL = 0; reg230[4]
Figure 9. I²C Programming Procedure
Rev. 0.6
21