ITech IT6600C Series User Manual page 47

NOTE
Voltage
Level
600V
1200V
The heavy solid line illustrates the locus of possible operating points as a
function of output. As shown by the horizontal portion of the line, the output
voltage remains regulated at its programmed setting as long as the load current
remains within the positive or negative current limit setting. A CV status flag
indicates that the output voltage is being regulated and the output current is
within its limit settings.
Note that when the output current reaches either the positive or negative current
limit, the unit no longer operates in constant voltage mode and the output voltage
is no longer held constant. Instead, the unit will now regulate the output current
at its current limit setting.
As shown by the vertical portions of the shaded quadrants, the output voltage
may continue to increase in the positive direction or decrease in the negative
direction as current is forced into or pulled out of the unit. When the output
voltage exceeds the over-voltage protection setting, the output will shut down.
CC Priority
In CC priority mode, the output is controlled by a bi-polar constant current
feedback loop, which maintains the output source or sink current at its
programmed setting. The output current remains at its programmed setting,
provided the load voltage remains within the voltage limit setting. CC priority
mode is best suited for use with batteries, power supplies, large charged
capacitors, and loads that are sensitive to current overshoots. It minimizes
current overshoots during programming, turn-on, and turn-off transitions and
seamlessly transitions between positive and negative currents.
In CC priority mode, the output current should be programmed to the desired
positive or negative value. A positive voltage limit range should also be set. The
voltage upper limit should always be set to a value that is greater than the actual
input voltage requirement of the external load. The following figure shows the
CC priority operating locus of the output. The area in the white quadrants shows
the output as a source (sourcing power). The area in the shaded quadrants
shows the output as a load (sinking power).
In sink mode, there is a minimum operating voltage. The minimum operating voltage
specification data corresponding to different voltage models are as follows.
Sink Current
-Imax
-Imax
Copyright ©ITECH Electronic Co., Ltd.
Minimum Operating
Voltage (MOV)
3V
6V
Power Supply Function
MOV/Vmax(%)
0.5%
0.5%
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