SWRA574B October   2017  – February 2020 AWR1243 , AWR2243

 

  1.   AWR2243 Cascade
    1.     Trademarks
    2. 1 Cascaded AWR2243 System
    3. 2 Synchronization of AWR2243 Chips
      1. 2.1 20 GHz (FMCW) RF LO Sync
      2. 2.2 Digital Frame Sync
        1. 2.2.1 Frame (Burst) and Chirp Timing in AWR2243
        2. 2.2.2 Frame (Burst) and Chirp Timing in a Cascaded System
        3. 2.2.3 Inter Chip Imbalance of Digital Sync Timing
      3. 2.3 40 MHz (System) Reference Clock Synchronization
    4. 3 Connectivity
      1. 3.1 20 GHz LO Sync Pins Connectivity
      2. 3.2 DIG_SYNC Connectivity
      3. 3.3 40 MHz (System) Reference Clock Connectivity
    5. 4 20 GHz LO Sync Link Budget
    6. 5 Software Messaging
      1. 5.1 Configuration of Devices
      2. 5.2 Configuration of Frames
        1. 5.2.1 Similar Configuration Across AWR2243 Devices
        2. 5.2.2 Dissimilar Configuration Across AWR2243 Devices
      3. 5.3 Triggering of Frames
      4. 5.4 Example Usage
      5. 5.5 Other Usages
    7. 6 Advantages of AWR2243 Cascading System
    8. 7 References
  2.   Revision History

3.1 20 GHz LO Sync Pins Connectivity

Table 2 shows the recommended combinations of pins to be used in 20 GHz LO sync on Master chip when the LO feeds back into the same chip.

Table 2. Recommended Combinations of Pins to be Used in 20 GHz LO

Combination Master LO Output Master LO Input Ground
1 FM_CW_SYNCOUT [D1] FM_CW_SYNCIN2 [D15] FM_CW_SYNCIN1 [B1]
2 FM_CW_CLKOUT [B15] FM_CW_SYNCIN1 [B1] FM_CW_SYNCIN2 [D15]

General guidelines on 20 GHz routing:

  • Keep the LO routing distance as small as possible.
  • LO Input ports: There are two LO input ports. These are labeled FM_CW_SYNCIN1 and FM_CW_SYNCIN2. These two ports are provided to aid routing of the LO distribution on the PCB. Only one input port can be used at a time. The unused port must be shorted to ground directly at the BGA
  • LO Output Ports: There are two LO output ports. Either port can be used or both ports can be used. Unused LO output ports should be left floating at the BGA pad.