I would like to use the LT3759 as a 15V -> -5V converter. The synchronization frequency will be adjusted by an FPGA during operation between 500-700 kHz to minimize interference with other components.
The datasheet indicates that the timing resistor, Rt, should be set to 20% lower than the SYNC frequency. Since the SYNC frequency will be changing during operation, what circuitry is recommended to replace Rt? If I choose an intermediate value, such as 13.7 kOhm for 600 kHz, will the part be able to sync properly over the range?