Vicor Constant Current (CC) Demonstration Board - Manual (Page 12)

UG:007 vicorpower.com Applications Engineering: 800 927.9474 Page 12
Figure 13
Resistive Load PRM Start Up
Waveform
Figure 14
CC & VTM Electronic /
Resistive Load
Figures 11 – 13 are taken in reference to –IN. Figures 15 – 19, showing the output voltage and
current ripple, were captured in reference to –OUT by using the scope jack (J02) for better accuracy.
3.5 CC Demonstration Board / VTM with an Electronic /
Resistive Load
1. Make sure that the power is removed from the unit prior to making adjustment.
2. Use output connector (J01) to connect the CC to the VTM-CB.
3. Connect DMM and a resistor network or electronic load in series with the output of the
VTM customer board. Make sure DMM can handle the maximum PRM output current
then set it to read DC current.
4. Verify proper electronic load and VTM connections.
5. Connect an oscilloscope to the test point provided to monitor output voltage on the
VTM-CB. The VTM provides current multiplication and source isolation. Grounding the
oscilloscope probe at the VTM –OUT and the PRM –IN will only provide a short path for
the AC current which will not affect the functionality of the system.
DC
+ +
- -
CCBD-CC
+
-
Electronic Load
+OUT
DMM
Measuring
Output Current
Set to Constant Resistance mode
DMM
Measuring Voltage V REF
using test point TP5
+ +
- -
VTM-CB
–OUT –IN
+IN
V REF
PRM I OUT
PRM PC
PRM V OUT