2
dc2195bf
DEMO MANUAL DC2195B
QUICK START PROCEDURE
DC2195B is easy to set up to evaluate the performance of
the LT8609/LT8609A. Refer to Figure 4 for proper measure-
ment 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 DC2195B’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 terminal
when SYNC function is used (JP1 on the SYNC posi-
tion). Please ensure that the chosen R
T
sets the LT8609/
LT8609A switching frequency to equal or below the
lowest SYNC frequency. See the data sheet section,
“Synchronization.”
Figure 1. Efficiency vs Load Current at 12V Input 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
LT8609A
LT8609
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