2
dc2195afb
DEMO MANUAL DC2195A
Quick start proceDure
DC2195A is easy to set up to evaluate the performance
of the LT8609. Refer to Figure 4 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. See Figure 5 for the proper scope
technique.
1. Set an input power supply that is capable of 42V/2A.
Then turn off the supply.
2. With power off, connect the supply to the input terminals
V
EMI
and GND.
3. Turn on the power at the input.
NOTE: Make sure that the input voltage never exceeds 42V.
4. Check for the proper output voltage of 5V. Turn off the
power at the input.
5. Once the proper output voltage is established, connect
a variable load capable of sinking 2A at 5V to the output
terminals V
OUT
and GND. Set the current for 0A.
a. If efficiency measurements are desired, an ammeter
can be put in series with the output load in order to
measure the DC2195A’s output current.
b. A voltmeter can be placed across the output terminals
in order to get an accurate output voltage measurement.
6. Turn on the power at the input.
NOTE: If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
7. Once the proper output voltage is again established,
adjust the load and/or input within the operating range
and observe the output voltage regulation, ripple volt-
age, efficiency and other desired parameters.
8. An external clock can be added to the SYNC ter-
minal when SYNC function is used (JP1 on the
SYNC position). Please ensure that the chosen R
T
sets the LT8609 switching frequency to equal or
below the lowest SYNC frequency. See the data
sheet section, “Synchronization.”
Figure 1. Efficiency vs Load Current at 2MHz Switching Frequency
I
OUT
(A)
0
EFFICIENCY (%)
100
90
70
80
60
95
75
55
85
65
50
1.5
DC2195 F01
2
1
0.5
12V INPUT
24V INPUT
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