GW Instek PSU Series - Page 25

GETTING STARTED
25
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.
Conversely the power supply will operate in CC
mode when the load resistance is less than the
critical resistance. In CC mode the current output
is equal to I
SET
and the voltage output is less than
V
SET
.
R
L=
R
C
R
L
<R
C
VSET
ISET
CV
CC
V
I
R
L
>R
C
Crossover
point
Note
For loads that generate a transient surge voltage, VSET
must be set so that the surge voltage does not reach
the voltage limit.
For loads in which transient peak current flows, ISET
must be set so that the peak value does not reach the
current limit.