Quick Start Procedure - Linear Technology DC1881A Demo Manual

DEMO MANUAL DC1881A

QUICK START PROCEDURE

Demonstration circuit 1881A is easy to set up to evaluate
the performance of the LTC3789. Refer to Figure 1 for
the proper measurement equipment setup and follow the
procedure below:
1. With power off, connect the input power supply to V
(6V to 36V) and GND (input return).
2. Connect the 12V output load between V
(Initial load: no load).
3. Connect the DVMs to the input and outputs.
4. Turn on the input power supply and check for the proper
output voltages. V
OUT
5. Once the proper output voltages are established, ad-
just the loads within the operating range and observe
the output voltage regulation, ripple voltage and other
parameters.
2
and GND
OUT
should be 12V ±2%.
Figure 1. Proper Measurement Equipment Setup
Note: When measuring the output or input voltage ripple,
do not use the long ground lead on the oscilloscope probe.
See Figure 2 for the proper scope probe technique. Short,
stiff leads need to be soldered to the (+) and (–) terminals
of an output capacitor. The probe's ground ring needs to
IN
touch the (–) lead and the probe tip needs to touch the
(+) lead.
Additional Notes:
1. Usually, the worst case efficiency at full load is at 6V
The board can deliver more output power at higher V
2. R2 is needed for additional/constant output current
limit only.
.
IN
.
IN
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