Receive Startup; Added Transmit Load Override Section, Receive Startup Section, Bypassing The Ram Section, Enabling Receive Channels Section, Setting Receive Bias Currents Section, Figure 13, Figure 14, Figure 15, And Figure 16 - Analog Devices ADAR1000-EVALZ User Manual

UG-1283
Transmit Load Override
For the gain and phase changes to take effect, a load transmit
override command must be given. To give this command, take
the following steps:
1. Click the MISC tab (see Figure 13).
2. In the Over Ride section, click LDTX OVR.
Figure 13. Load Transmit Override

RECEIVE STARTUP

The following procedures bypass the RAM, enable receive
subcircuits, set the device to SPI control, place the device in
receive mode, and set Receive Channel 1 to maximum gain and
45° phase.
Bypassing the RAM
To bypass the on-chip RAM and source the gain and phase data
from the configuration register, take the following steps:
1. Click the MISC tab (see Figure 14).
2. Select the BEAM RAM BYPASS check box and the BIAS
RAM BYPASS check box.
3. Click Write Value.
Figure 14. Placing the Device in RAM Bypass Mode
Enabling Receive Channels
To enable the receive channels and associated circuits, take the
following steps:
1. Click the T/R Control tab (see Figure 15).
2. Select all check boxes in the Rx Enable section to enable all
four receive channels and the corresponding subcircuits.
3. Click Write Enable Values.
Setting Receive Bias Currents
To set the nominal bias currents for the receive VGAs, vector
modulators, and drivers, take the following steps:
1. Click the RX Registers tab (see Figure 16).
2. In the Bias Current section, set RX VGA BIAS to 2, set
RX VM BIAS to 6, and set LNA BIAS to 8.
3. Click Write Bias Values.
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ADAR1000-EVALZ
Figure 15. Enabling Receive Channels
Figure 16. Setting Receive Bias Currents
User Guide