To Next Page

To Previous Page

Power Supply Function

CC Priority

In CC priority mode, the output is controlled by a bi-polar constant current feed-

back 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 pro-

gramming, 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. For this series models,

the MOV corresponding to –Imax is about Vmax*2%.

The heavy solid line illustrates the locus of possible operating points as a func-

tion of output. As shown by the vertical portion of the line, the output current re-

mains regulated at its programmed setting as long as the output voltage

remains within its limit setting. A CC (constant current) status flag indicates that

the output current is being regulated and the output voltage is within its limit

settings.

ITech IT-M3900C Series User Manual

Questions and Answers: