Texas Instruments DS90UB925QSEVB, User Manual, Page: 3 / 36

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Sept 2012 Literature Number: SNLU113 3
1.3. Operation – Quick Setup
Make sure S1, S2, S3, S4, and JP2 are configured as shown in Figure 1.
1) Turn on the deserializer.
Typically this would be the DS90UB926Q EVB.
2) If interfacing to 3.3V LVCMOS, skip this step, otherwise:
when interfacing to 1.8V LVCMOS inputs (upstream device), move factory jumper from pin-2/3 to pin 1 to
connect to pin-1/2 and apply 1.8V power to pin 1 of JP1. This will connect the external 1.8V to the
DS90UB925Q VDDIO, otherwise skip this step.
3) Apply 3.3V power to the DS90UB925Q VDD.
4) Look for the green LED2 to light up on the DS90UB926Q EVB. If the green LED is lit and stable, then the
DS90UB926Q is LOCKED to the FPD-Link III serial stream. To be absolutely sure the DS90UB926Q is
locked, use a scope to monitor off JP6 (pin 1 = LOCK, pin 2 = VSS) of the DS90UB926QSEVB.
CONGRATULATIONS, you are up and running!
If not continue to the next step…
1.4. Trouble Shooting the EVB
1) Check power supply polarity!!! Warning: reverse supply polarity can damage the board.
2) Check to make sure there is sufficient current by checking that the voltage (3.3V) is correct at J6.
3) Check polarity of SER to DES cable interface. e.g. SER DOUT+ is going to RIN+ of DES and vice versa.
4) Check to make sure there is a FPD-Link III signal by probing on
both C9 AND C10.
5) Go back to figure 1 and double check factory settings.
3.3V