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.