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dc607afa
DEMO MANUAL DC607A
Quick start proceDure
Demonstration circuit 607A is easy to set up to evaluate
the performance of the LTC3722, LTC4440, LTC3901,
and LT1431. Refer to Figure 1 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. Measure the output (or input) voltage
ripple by touching the probe tip and probe ground directly
across the +Vout and –Vout (or +Vin and –Vin) terminals
or input/output capacitors. See Figure 2 for proper scope
probe technique.
1. Set an input power supply that is capable of 36V to 72V
to a voltage of 36V. Then turn off the supply.
2. With power off, connect the supply to the input terminals
+Vin and –Vin.
a. Input voltages lower than 36V can keep the converter
from turning on due to the undervoltage lockout
feature of the LTC3722.
b. If efficiency measurements are desired, an ammeter
capable of measuring 15Adc or a resistor shunt can
be put in series with the input supply in order to
measure the DC607A’s input current.
c. A voltmeter with a capability of measuring at least
72V 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
72V.
4. Check for the proper output voltage of 12V ±1%. Turn
off the power at the input.
5. Once the proper output voltage is established, connect
a variable load capable of sinking 35A at 12V to the
output terVout and –Vout. Set the current
for 0A.
a. If efficiency measurements are desired, an ammeter
or a resistor shunt that is capable of handling 35Adc
can be put in series with the output load in order to
measure the DC607A’s output current.
b. A voltmeter with a capability of measuring at least 12V
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 within the operating range and observe
the output voltage regulation, ripple voltage, efficiency
and other desired parameters.
