Texas Instruments DAC3484, DAC3482 installation instructions Digital Block Options

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2.2.2Digital Block Options

Figure 4. Digital Block Options

●Interpolation: allows control of the data rate versus DAC sampling rate ratio (i.e. data rate × interpolation = DAC sampling rate).

●Digital Mixer: allows control of the coarse mixer function.

Note: If fine mixer (NCO) is used, the “Enable Mixer” button must be checked, and the coarse mixer must be bypassed. See NCO section for detail.

●Inverse sinx/x filter: allows compensation of the sinx/x attenuation of the DAC output.

Note: If inverse sinx/x filter is used, the input data digital full-scale must be backed off accordingly to avoid digital saturation.

●Clock Receiver Sleep: allows the DAC clock receiver to be in sleep mode. The DAC has minimum power consumption in this mode.

●Clock Divider Sync: allows the syncing of the internal divided-down clocks using either Frame, Sync, or OSTR signal. Enable the divider sync as part of the initialization procedure or resynchronization procedure.

●Group Delay: allows adjustment of group delay for each I/Q channel. This is useful for wideband sideband suppression.

●Offset Adjustment: allows adjustment of DC offset to minimize the LO feed-through of the modulator output. This section requires sync for proper operation. The sync options are listed below:

O REGWR: auto-sync from SIF register write.

OOSTR: sync from the external LVPECL OSTR signal. Clock divider sync must be enabled with OSTR set as sync source

O SYNC: sync from the external LVDS SYNC signal.

OSIF SYNC: sync from SIF Sync. Uncheck and check the SIF Sync button for sync event.

●QMC Adjustment: allows adjustment of the gain and phase of the I/Q channel to minimize sideband power of the modulator output.

OREGWR: auto-sync from SIF register write.

OOSTR: sync from the external LVPECL OSTR signal. Clock divider sync must be enabled with OSTR set as sync source

O SYNC: sync from the external LVDS SYNC signal.

OSIF SYNC: sync from SIF Sync. Uncheck and check the SIF Sync button for sync event.

SLAU336 –March 2011	DAC3484/DAC3482 EVM	5
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