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dc1877af
DEMO MANUAL DC1877A
Quick start proceDure
This demonstration circuit 1877A can be evaluated using
the setup shown in Figure 1.
1. Connect the DVMs to the input and output. Select 5V
setting using jumper JP1 (B position) and JP2 (A posi-
tion), select ON position for JP3.
2. With input power supply set for 0V, connect the supply to
V
IN
and GND terminals using short (less than 10 inches)
leads, preferably twisted leads. Connect a suitable load
to V
OUT
and GND terminals.
3. Slowly increase the input power supply to 10V. Observe
output voltage and verify that it meets the specifications
in Table 1. Measure output voltage with and without the
load.
4. Move jumpers JP1 and JP2 to the other two fixed volt-
age settings and verify that each output voltage meets
the values as shown in Table 1.
5. Once the proper output voltages are established, adjust
the load and input voltage within the operating range
and observe the output voltage regulation, ripple voltage
and other parameters.
Notes:
1. IMPORTANT: 60V or higher voltage can result in an
electric shock if care is not taken. Also, hot plugging
the circuit to a power supply that has more than 40V
present at its output can produce a high voltage transient
exceeding the absolute maximum input voltage which
can damage the LTC3630A.
2. 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
ripple by touching the probe tip directly across the V
IN
or V
OUT
and GND terminals. See Figure 2 for proper
scope probe technique.
Figure 1. Proper Measurement Equipment Setup
Load
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