2260B Series User Manual
20
CC and CV Mode
CC and CV mode
Description
When the power supply is operating in
constant current mode (CC) a constant current
will be supplied to the load. When in constant
current mode the voltage output can vary,
while the current remains constant. When the
load resistance increases to the point where the
current limit (I
SET
) can no longer be sustained
the power supply switches to CV mode. The
point where the power supply switches modes
is the crossover point.
When the power supply is operating in CV
mode, a constant voltage will be supplied to
the load, while the current will vary as the load
varies. At the point that the load resistance is
too low to maintain a constant voltage, the
power supply will switch to CC mode and
maintain the set current limit.
The conditions that determine whether the
power supply operates in CC or CV mode
depends on the set current (I
SET
), the set voltage
(V
SET
), the load resistance (R
L
) and the critical
resistance (R
C
). The critical resistance is
determined by V
SET
/I
SET
. The power supply
will operate in CV mode when the load
resistance is greater than the critical resistance.
This means that the voltage output will be
equal to the V
SET
voltage but the current will be
less than I
SET
. If the load resistance is reduced
to the point that the current output reaches the
I
SET
level, the power supply switches to CC
mode.