Texas Instruments DAC3482, DAC3484 installation instructions Output Control Options

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●NCO: allows fine mixing of the I/Q signal. The procedure to adjust the NCO mixing frequency are listed below:

1.Enter the DAC sampling frequency in Fsample.

2.Enter the desired mixing frequency in both NCO freq_AB and NCO freq_CD.

3.Press Update freq

4.Sync the NCO block from the following options:

●REGWR: auto-sync from SIF register write. Writing to either Phase OffsetAB or Phase OffsetCD can create a sync event.

●OSTR: sync from the external LVPECL OSTR signal. Clock divider sync must be enabled with OSTR set as sync source. Refer to the datasheet for OSTR period requirement.

●SYNC: sync from the external SYNC signal

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

2.2.3Output Control Options

Figure 5. Output Control Options

●Output Options: allows the configuration of reference, output polarity, and output delay

●Data Routing: provides flexible routing of the A, B, C, and D digital path to the desired output channels.

Note: The DAC3482 does not support this mode.

●DAC Gain: configures the full-scale DAC current and DAC3484/DAC3482 mode. With Rbiaj resistor set at 1.28kΩ:

O DAC Gain = 15 for 30mA full-scale current.

ODAC Gain = 10 for 20mA full-scale current (default). O DAC3484 = QDAC

O DAC3482 = DDAC

●This allows the DAC3484 to be configured as DAC3482 (see Using DAC3484 as DAC3482 section for detail)

●DAC Sel = Enable inner outputs of Ch. B and Ch. C as the DAC3482 output.

●DAC Sel = Enable outer outputs of Ch. A and Ch. D as the DAC3482 output. Outer channels are grounded for the DAC3482 device.

●Output Shutoff On: allows outputs to shut-off when DACCLK GONE, DATACLK GONE, or FIFO COLLISION alarm event occurs.

6	DAC3484/DAC3482 EVM	SLAU336 –March 2011
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