Linear Technology DC2142A Demo Manual page 2

DEMO MANUAL DC2142A
Quick start proceDure
Demonstration circuit 2142A is easy to set up to evaluate
the performance of the LTC3875EUJ and LTC3874IUFD.
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
(4.5V to 14V) and GND (input return).
2. Connect the 1.0V output load between V
(Initial load: no-load).
3. Connect the DVMs to the input and outputs. Set default
jumper position: JP1: CCM; SW1: ON.
4. Turn on the input power supply and check for the proper
output voltages. V
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OUT
should be 1.0V ±2%.
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.
Note: When measuring the output or input voltage ripple,
IN
do not use the long ground lead on the oscilloscope probe.
See Figure 2 for the proper scope probe technique. Short,
and GND
stiff leads need to be soldered to the (+) and (–) terminals
of an output capacitor. The probe's ground ring needs to
touch the (–) lead and the probe tip needs to touch the
(+) lead.
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