Frequency Sweeping Q: What type of frequency sweeping is available?
• Linear ramp with defined endpoints – (commonly called ramped FSK). The user is able to program a beginning and terminating frequency. The user can then specify an incremental frequency and the rate at which to increment the frequency. Upon reaching the terminating frequency the device may either hold the terminating frequency value (standard), or return to the starting frequency instantaneously (return-to-zero). • Linear sweep with no defined endpoints – As with ramped FSK, the user can specify an incremental frequency value and the rate at which to increment the frequency. However, as there are no defined endpoints, once the sweep begins, it only stops when the user indicates a stop, either via a pin control (HOLD pin on AD9852) or by writing to one of the registers a zero value. The user can also clear the “Linear Sweep Enable” bit in the control register for the device, but this clears all information from the linear sweep registers, and the frequency immediately returns to the va
