_________________________________________________________________________________________DS3106DK
1.1
Input and Output Clocks
There are two SMB connectors at the left of the board labeled IC3 and IC4 that provide a single-ended clock input
to the DS3106. These clock inputs are connected to the DS3106 with a 50 Ω characteristic impedance trace and
terminated with 50 Ω at the device.
On the other side of the PCB are three SMB clock output connectors labeled OC3, FSYNC, and MFSYNC. All
single-ended clock outputs are buffered at the DS3106 and connected to the SMB connector via a 50 Ω
characteristic impedance trace. Two additional SMB connectors labeled OC6P and OC6N provide connections to
the OC6 differential output from the DS3106.
1.2
Jumpers, Headers, and Switch Settings
Jumpers JMP9 to JMP12 and JMP16 (lower right of board) provide the means to pull up or pull down the
O3F1/SRFAIL, O3F2/LOCK, SRCSW, SONSDH, and TEST pins of the DS3106. Labels specify which position is
used to pull each pin to a 1 or a 0 (if jumper is not installed pin is left to float to accommodate a pin’s output
function). Jumpers JMP1 to JMP4 (middle right of board) provide access to the IPF0/SYNC1, IPF1/SYNC2,
IPF2/IC9, and O3F0/SYNC3 pins of the DS3106. Labels specify the position to install the jumper to pull the pin up
(signified by “1”) or pull it down through a 50 Ω resistor (signified by “TERM\0”). The 50 Ω resistor is used as a
termination resistor when the pin is used as a input clock signal. Jumper JMP6 (labeled VDDIOB) is not used in the
DS3106DK. Jumpers JMP62 and JMP63 select the computer interface to be USB or RS232. Jumper JMP5 (upper
left) selects whether the board should be powered from the USB connector or from the power-supply jacks (J3 or
J13/J19). LEDs DS1–DS4 (upper left) indicate the labeled power supply is operational. LED DS16 (upper right)
indicates the microprocessor is operational. LEDs DS5, DS6, and DS10 (lower middle) indicate the status of
SRFAIL, LOCK, and INTREQ pins, respectively. Switch SW1 is used to select a squaring circuit to accommodate a
sinusoidal input on IC3. Header J51 provides access to the JTAG port of the DS3106. Test points are provided for
differential the differential output (OC6), SPI port pins, ground plane connection, and pings O6F0/GPIO1,
O6F1/GPIO2, O6F2/GPIO3.
1.3
Microcontroller
The DS87C520 microcontroller has factory-installed firmware in on-chip nonvolatile memory. This firmware
translates memory access requests from the RS232 serial port or USB port into register accesses on the DS3106.
When the microcontroller starts up it turns on DS16 to indicate that the controller is working correctly. A pushbutton
switch labeled RESET near the RS232 connector resets the microcontroller as well as the DS3106.
1.4
Power-Supply Connectors
A 5V lab power supply can be connected across the red (J13) and black (J19) banana jacks. Optionally the board
can be powered from the USB connector by placing jumper JMP5 in the USB position. The 5V input from any of
these sources is then regulated to 3.3V, 2.5V, and 1.8V and distributed to board components.
Note that the board cannot be USB powered through some USB hubs. Before trying to power the board through a
USB hub, check the voltage at JMP5 to ensure the board is getting 5V from the hub.
Rev: 012208
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