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dc1649afa
DEMO MANUAL DC1649A
TYPICAL DC1649A REQUIREMENTS AND CHARACTERISTICS
QUICK START PROCEDURE
PARAMETER
INPUT OR OUTPUT
PHYSICAL LOCATION
DETAILS
3.3V Power Supply
Input
J9 and J10 Banana Jacks
Low Noise and Spur-Free 3.3V, 95mA
5V Charge Pump Power Supply
Input
J11 and J12 Banana Jacks
Low Noise and Spur-Free 5V, 35mA
5V VCO Power Supply
Input
“V+VCO” Turret
Low Noise and Spur-Free 5V, 18mA
REF+, Reference Frequency
Input
J2 SMA Connector
Low Noise 10MHz or 100MHz*, 6dBm into
50Ω, See Note 1
REFO, Buffered Reference
Output
J1 SMA Connector
Frequency = f
REF
, 0dBm
RF+ and RF–
Two Outputs
J6 and J7 SMA Connectors
902MHz to 928MHz* in 250kHz* Steps, 0dBm
Loop Bandwidth
Set by Loop Filter Component Values
7kHz*
*These frequencies are for the “DC1649A-10MHz.pllset “or” DC1649A-100MHz.pllset” files and included VCO.
Note 1:
A low noise 10MHz or 100MHz reference frequency, such as the
Wenzel 501-04608A or 501-04516D OCXO, is recommended. If using a
different frequency, make sure to update the Fref and R_DIV boxes under
the System tab in PLLWizard so that Fpfd is still 250kHz. For example, if a
20MHz clock is used, Fref should be changed to 20MHz and R_DIV to 80.
Ref BST and FILT under the System tab in PLLWizard might need to be
changed if the reference frequency and/or power is different than what is
recommended in the table above. More information can be found in the
LTC6945 data sheet.
The DC590 and PLLWizard application are required to
control the DC1649A through a personal computer (PC).
DC590B Configuration
The DC590’s QuikEval™ drivers must be installed before
the DC590 will be able to communicate with the LTC6945.
To configure the DC590, follow the procedure below, start-
ing with Step 1. If you have already installed the DC590
software previously, skip to Step 5.
Note: Once the QuikEval software is installed, the applica-
tion
Does Not
need to be executed to run PLLWizard or to
control the DC1649A.
1. Do Not plug in the DC590 before running the installation
program.
2. Download the QuikEval installation program from
http://www.linear.com/software.
3. Run the QuikEval installation program and follow the
on-screen instructions. More detailed installation infor-
mation may be found in the DC590’s Quick Start guide.
4.
Exit the QuikEval program once the installation is com-
plete, as it is not needed to run the PLLWizard software.
5. Place the DC590 jumpers in the following positions:
JP4 - EE
Must be in the “EN” position.
JP5 - ISO
”ON” must be selected.
JP5 - SW
”ON” must be selected.
JP6 - VCCIO
“3.3V” must be selected. This sets the SPI
port to 3.3V operation.
6. Connect the DC590 to one of your computer’s USB
ports with the included USB cable.
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