2
dc1737af
DEMO MANUAL DC1737A
QUICK START PROCEDURE
Demonstration circuit 1737 is easy to set up to evaluate
the performance of the LTC3863. Refer to Figure 1 for
proper measurement equipment setup and follow the
procedure below:
Note: When measuring the output voltage ripple, care must
be taken to avoid a long ground lead on the oscilloscope
probe. Measure the output voltage ripple by touching the
probe tip and ground ring directly across the last output
capacitor as shown in Figure 1.
1. Set an input power supply that is capable of 4.5V to
16V to 5V. Then turn off the supply.
2. With power off, connect the supply to the input terminals
+VIN and –VIN.
a. Input voltages lower than 4.5V can keep the converter
from turning on due to the undervoltage lockout
feature of the LTC3863.
b. If efficiency measurements are desired, an ammeter
capable of measuring 2A DC or a resistor shunt can
be put in series with the input supply in order to
measure the DC1737A’s input current.
c. A voltmeter with a capability of measuring at least
16V can be placed across the input terminals in order
to get an accurate input voltage measurement.
3. Turn on the power at the input.
Note: Make sure that the input voltage never exceeds 16V.
4. Check for the proper output voltage of –5.2V. Turn off
the power at the input.
V
–
+
V
–
+
V
OUT
V
IN
V
IN
I
OUT
LOAD
+
–
A
–
+
I
IN
A
–
+
+
Figure 1. Proper Measurement Equipment Setup
