27.4 Carrier Synchronization

During the time when the DSM switches between carrier high and carrier low signal sources, the carrier data in the modulated output signal can become truncated. To prevent this, the carrier signal can be synchronized to the modulator signal. When synchronization is enabled, the carrier pulse that is being mixed at the time of the transition is allowed to transition low before the DSM switches over to the next carrier source.

Synchronization is enabled separately for the carrier high and carrier low signal sources. Synchronization for the carrier high signal is enabled by setting the CHSYNC bit. Synchronization for the carrier low signal is enabled by setting the CLSYNC bit.

The figures below show the timing diagrams of using various synchronization methods.

Figure 27-2. On Off Keying (OOK) Synchronization
Figure 27-3. No Synchronization (MDCHSYNC = 0, MDCLSYNC = 0)
Figure 27-4. Carrier High Synchronization (MDCHSYNC = 1, MDCLSYNC = 0)
Figure 27-5. Carrier Low Synchronization (MDCHSYNC = 0, MDCLSYNC = 1)
Figure 27-6. Full Synchronization (MDCHSYNC = 1, MDCLSYNC = 1)