Teledyne SP Devices ADQ7DC, Manual

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19-2233 PC2
2019-02-01
9(50)
ADQ7DC Manual
16-1796 PC2 2019-02-01
9(50)
2 SETTING UP THE ANALOG FRONT-END
2.1 AFE block diagram
The analog front-end setup for ADQ7DC is found in Figure 2 .
The ADQ7DC can operate with two channels at 5 GSPS or one channel at 10 GSPS. To change mode
of operation, the single or dual channel firmware has to be activated by using the ADQ7 Updater tool
1
.
For more information, see [6] . Note that there are different connectors for the single and dual channels
mode. This means that one detector for 10 GSPS can be connected to the channel X at the same time
as two slower detectors are connected to channel A and B.
The switch between the 1 analog input channel and 2 analog input channels modes is set in the correct
state when loading the firmware. The switch may also be controlled from software
2
. The front-end
switch can be used for protecting the input. By switching to the un-used input, the switch can discon-
nect the detector during certain risky operations like power up/down of detectors.
2.2 Set analog DC-offset
A user-controlled DC-offset is available. The analog DC-offset is applied to the signal to better adopt to
the signal range of the digitizer. The analog range is by default set symmetrical around zero. If the sig-
nal is unipolar or heavily unsymmetrical, the DC-offset function can adjust the signal to an optimal verti-
# DESCRIPTION USER COMMAND REF
a The analog input is terminated 50 ohms to GND.
b Switching between 1 and 2 channels. Load the correct firmware using
ADQ7 updater tool. This will set the input switch.
The input switch can also be controlled by a software command for
disconnecting the input.
Note that this command do not change the ADQ7
from 1 to 2 channels acquisition.
SetAfeSwitch 2.1
c Set a DC-offset for better using the signal range when the signal is
unipolar. Changing the DC-offset requires a settling time of 1 s. SetAdjustableBias 2.2
d The gain and offset are calibrated at DC. The digital compensation
corrects the offset and the gain at this condition. The user can access this
function to set a different gain and offset. SetGainAndOffset 2.3
Figure 2: ADQ7 AFE control.
1. Note that there is one ADQ7 updater tool for ADQ7 and another ADQ updater for other ADQ digitizers.
2. Note that the software switch only changes the input. To change function, the firmware has to be loaded.
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