Chapter 7 Tutorial
Output Characteristics
144
Figure 7-5 shows the operating modes of the output of the Agilent E3632A
power supply. The operating point of one supply will be either above or below
the line RL = RC. This line represents a load where the output voltage and the
output current are equal to the voltage and current setting. When the load RL
is greater than RC, the output voltage will dominate since the current will be
less then the current setting. The power supply is said to be in constant voltage
mode. The load at point 1 has a relatively high resistance value (compared to
RC), the output voltage is at the voltage setting, and the output current is less
than the current setting. In this case the power supply is in the constant voltage
mode and the current setting acts as a current limit.
Figure 7-5. Output Characteristics
When the load RL is less than RC, the output current will dominate since the
voltage will be less than the set voltage. The power supply is said to be in
constant current mode. The load at point 2 has a relatively low resistance, the
output voltage is less than the voltage setting, the output current is at the
current setting. The supply is in constant current mode and the voltage setting
acts as a voltage limit.