Agilent Technologies N3280A manual Output Characteristics, Voltage Priority Operation

General Information - 1

Output Characteristics

Voltage Priority Operation

Each Agilent N3280A output is a four-quadrant bipolar dc source that can be operated in either voltage or current priority mode. In voltage priority mode the output is controlled by a bi-polar constant voltage feedback loop, which maintains the output voltage at its positive or negative programmed setting. The output voltage will remain at its programmed setting as long as the load current remains within the positive or negative current limit. A single positive value programs both the positive and negative current limit.

Figure 1-1 shows the voltage priority operating characteristics of the dc source. The area in quadrants 1 and 3 shows the characteristics of the output when it is being operated as a source (sourcing power). The area in quadrants 2 and 4 shows the characteristics of the output when it is being operated as a load (sinking power).

	Output	Key
	Voltage	Sinking power
+ OV	+	Sourcing power
+ 10.25V		Programmable
-I limit
		V setting
-	2 1	+ Output
	3 4	Current
		+I limit
- 10.25V		+ 512.5mA
- 512.5mA
	-	- OV

Figure 1-1. Output Characteristic (Voltage Priority)

The heavy line illustrates the locus of possible operating points as a function of the output load, which may be purely resistive, or possibly include external voltage or current sources. In voltage priority mode, the constant voltage loop will regulate the output voltage as the load changes, unless the output current attempts to exceed the current limit setting.

If this occurs, either the negative or the positive current limit loop will regulate the output current at the programmed value. Either a CV (constant voltage), CL+ (positive current limit), or CL− (negative current limit) status flag is set to indicate which loop is presently controlling the output.

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