Vicor Constant Current (CC) Demonstration Board User Manual
Page 11
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Page 11
Figure 11
Electronic Load Constant
Resistance PRM
Start Up Waveform
The following Figures 11 - 13 are a start up comparison between what the user should see when
using an electronic load and an actual equivalent power resistor. Figure 11 shows a delay in the
PRM output current introduced by the electronic load set to 0.16 s along with a current overshoot.
Note: do not set the electronic load in a constant voltage mode is not recommended for stability
reasons. If the electronic load is set to a constant voltage, a lengthier delay and an unstable
behavior is observed as in Figure 12. These plots are presented to inform the user of the possible
occurrence of this issue when exploring the CC demo board.
The current overshoot occurs within that instant where the CC senses and corrects its response.
Using a resistive load equivalent to 7
Ω, Figure 13 shows the expected waveform where both the
reference voltage and the PRM output current agree. Please refer to the start up sequencing
section in the
for more details on the rise time limitations.
Figure 12
Electronic Load Constant
Voltage PRM
Start Up Waveform
V
REF
PRM I
OUT
PRM PC
PRM V
OUT
V
REF
PRM I
OUT
PRM PC
PRM V
OUT