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dc1733af

DEMO MANUAL DC1733A

QUICK START PROCEDURE

Demonstration circuit 1733A is easy to set up to evaluate

the performance of the LT3669 or the LT3669-2. Refer to

Figure 1 for proper measurement equipment setup and

follow the procedure below:

NOTE. When measuring the input or output voltage ripple,

care must be taken to avoid a long ground lead on the

oscilloscope probe. Measure the input or output voltage

ripplebytouchingtheprobetipdirectlyacrosstheterminals

of the input or output capacitors. See Figure 2 for proper

scope probe technique.

1. Place jumpers in the proper positions.

2. With power off, connect an input power supply to

L+  and  L–/GND. The input supply can be a bench

power supply or can be from the respective output

from a master controller.

5. Turn on the power at the input.

6. Check for the proper output voltages.

NOTE. If there is no output, temporarily disconnect

the load to make sure that the load is not set too high

or is shorted.

7. Once the proper output voltage is established, adjust

the loads within the operating range and observe the

outputvoltageregulation,ripplevoltage,efficiencyand

other parameters.

8. To test driver and receiver functions, use JP8 to JP11

to set up the proper signal sources or levels for TXEN1,

TXEN2, TXD1, and TXD2.

9. Set up or monitor other signals as needed.

10. Once the above signals are set up, observe driver’s

outputs and receiver’s inputs and outputs.