Evaluation Board Hardware; Package Contents; Requirements; Setting Up The Evaluation Board - Analog Devices AD9959/PCB Manual

EVALUATION BOARD HARDWARE

PACKAGE CONTENTS

The AD9959/PCB kit contains the following:
•
AD9959 evaluation board
•
AD9959/PCB installation software

REQUIREMENTS

In order to successfully use the evaluation board and run the
software, the requirements listed in Table 1 must be met.
Table 1. AD9959/PCB Requirements
Item Requirement
Operating System Windows® 98/Me/2000/XP
Processor Pentium® I or better
Memory 128 MB or better
Ports One USB port
Clocking Signal generator capable of generating
sinusoidal waves of at least 3 dBm power,
up to at least 10 MHz
Power Supplies Capability to generate at least 2
independent dc voltages (1.8 V/3.3 V)
Measurement Appropriate measurement device, such as
a spectrum analyzer or a high bandwidth
oscilloscope
Cables USB 1.1/2.0 cable, and SMA-to-X cables
(X = SMA or BNC, depending on the
connector of the device interfacing with
the board)

SETTING UP THE EVALUATION BOARD

Powering the Part

The AD9959 evaluation board has seven power supply
connectors: TB1, J10, J16, J17, J18, J19, and J20. TB1 powers the
DDS, the PC interface logic, and the USB circuitry. J10 powers
the input clock circuitry. J18 provides the reference voltage
needed for band gap functionality. J16, J17, J19, and J20 power
the analog circuitry of individual DACs. It is important to keep
in mind that the AD9959 evaluation board has been pre-
configured so that these four AVDD connections (J16, J17, J19,
and J20) are tied together. Supplying power to any one of the
AVDD connections allows for the proper functionality of the
analog circuitry of all four DACs. Table 2 shows the necessary
connections and the appropriate biasing voltage.
Table 2. Connections and Biasing Voltage
Connector
TB1
TB1
TB1
TB1
J10
J16
J17
J18
J19
J20
Note that the AD9959/PCB is preconfigured so that the
CLK_VDD, BG_VDD, and all other AVDD connections are
tied together. Therefore, only one connection (J10, J16, J17, J18,
J19, or J20) needs power for proper functionality of all four
channels. These AVDD connections can be separated for better
channel isolation. This is accomplished by removing the 0 Ω
resistors (R21, R32–R51, R54–R64) that tie the planes together
found on the back of the evaluation board. When doing this, be
sure that CLK_VDD, BG_VDD, and the AVDD connection for
all desired channel(s) are powered.

Clocking the Part

The AD9959 architecture provides the user with two options when
providing an input signal to the part. Figure 1 shows that the user
can clock the frequency synthesizer/DDS directly by connecting
an external clocking signal to the REF CLK connector, J9, or by
providing an external crystal. Place jumper W11 on REF CLK
to use the external clocking option. To use an external crystal as
the clocking source, place jumper W11 on CRYSTAL.
Please refer to the AD9959 data sheet for details on the maximum
input speeds and input sensitivities of these two inputs.

Communicating with the Part

Two interface standards are available on the evaluation board:
1. USB 1.1/2.0 interface.
2. Header row (U2, U13), which places the part under the
control of an external controller (such as a µP, FPGA, or DSP).
Analog Devices provides a GUI for the PC; it does not provide
control software for external controllers.
Use the jumper settings listed in Table 3 to enable different
modes of communication.
Table 3. Jumper Settings for Communication Modes
Mode
PC control, USB port
External control
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AD9959/PCB
Pin No. Label
1 VCC_USB
2 DVDD_I/O
3 GND
4 DVDD
CLK_VDD
AVDD
AVDD
BG_VDD
AVDD
AVDD
Settings
Set W7 to PC. Place a jumper on W1,
W2, W3, W9, and W10.
Set W7 to manual. Place a jumper on
W9, and remove W1, W2, W3, and W10
(or leave it stored as a shunt).
Voltage (V)
3.3
3.3
0
1.8
1.8
1.8
1.8
1.8
1.8
1.8