4 Quick Start Procedure for Complex Decimation Mode
The ADC32RF5x device family provides up to two digital down converters (DDC) per ADC channel supporting a
wide range of instantaneous bandwidth IBW coverage - from single wide band mode with 8x complex decimation
to up to two narrow band channels with as high as 128x complex decimation.
When operating in complex decimation mode, the appropriate NCO is used as an intermediate frequency to
the complex mixer. Similar to the bypass operating mode, the user has the option to enable averaging of each
internal pair of ADCs. This section will provide two example configurations for operating the ADC32RF5xEVM in
8x and 128x decimation modes.
4.1 8x Complex Decimation
This example uses a coherent 790 MHz input on the channel A input with the ADC in a 1x averaging mode with
dither enabled.
Procedure
1. In the
Bypass Mode
box, use the DDC dropdown to change to
Complex Mode
. The usser will notice the
box title changes to
Complex Mode
to reflect the current DDC operating mode.
2. Use the
Decimation
dropdown to change the decimation to
8
.
3. Set the
LMFSHd
setting to
4-4-2-1-0.
4. Set the channel INA1
NCO0
and
NCO1
to 800 (MHz).
5. Change
LMK divider
from 8 to 16.
6. Once these settings are verified and match
, press the
Device Bringup
button.
Figure 4-1. ADC32RF5xEVM GUI, 8x complex decimation, 800 MHz NCO
7. Wait until after the message
Device Bringup Completed
appears in the Log.
Quick Start Procedure for Complex Decimation Mode
8
ADC32RF5xEVM User Guide
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