Texas Instruments DAC3484 用户手册
www.ti.com
Software Control
2.2.4
CDCE62005
Figure 6. CDCE62005 Tab Configured for 4x Interpolation
Clock frequency control is determined by register values in the CDCE62005 Control tab. Please refer to
the CDCE62005 datasheet for detailed explanations of the register configuration to change the clock
frequency.
the CDCE62005 datasheet for detailed explanations of the register configuration to change the clock
frequency.
The following CDCE62005 outputs are critical to proper operation of the DAC348x:
●
Y1: DAC348x FIFO OSTR clock. The clock rate for this should be at least F
DAC
/Interpolation/8 for
DAC3484 mode and DAC3482 mode.
O The whole OSTR clock equation needs to take account of both the Y1 CDCE62005 clock
divider ratio and the additional CDCP1803 divide-by-2 clock divider.
O This OSTR signal can be a slower periodic signal or a pulse depending on the application.
O Note: The FIFO OSTR clock should be disabled when the DAC348x is configured in PLL
mode.
●
Y2: DAC348x DAC sampling clock. If the DAC348x is configured for internal PLL mode, this will
be the reference clock input for the PLL block.
be the reference clock input for the PLL block.
●
Y3: TSW3100 FPGA clock. The clock rate for this should be F
DAC
/interpolation/2 for DAC3484
mode and F
DAC
/interpolation/4 for DAC3482 mode.
7
SLAU336 – March 2011
DAC3484/DAC3482 EVM
© 2011, Texas Instruments Incorporated