Agilent Technologies 90B manual Auto Tracking Operation, Auto-Tracking of Two Supplies

AUTO TRACKING OPERATION

Auto-Tracking or automatic tracking operation of power supplies is similar to Auto-Series operation except that the master and slave supplies have the same output polarity with respect to a common bus or ground. Figure 68 shows two supplies connected in Auto-Tracking with their negative output terminals connected together as a common or ground point. A fraction R2/(R1 + R2) of the output of the master supply is provided as one of the inputs to the comparison amplifier of the slave supply, thus controlling the slave's output. The master supply in an Auto-Tracking system must be the positive supply having the largest output voltage. Auto-Series addition of still more slaves permits the expansion of an Auto-Tracking system to both positive and negative power supplies.

Figure 68. Auto-Tracking of Two Supplies

Like Auto-Series operation, Auto-Tracking permits simultaneous turn-on and turn-off of power supplies in the same system, thereby preventing accidental application or removal of main power sources without proper bias potentials being present.

CONVERTING A CONSTANT VOLTAGE POWER SUPPLY TO CONSTANT CURRENT OUTPUT

Many, but not all, Agilent power supplies are capable of constant current operation. Those which are not designed for normal operation as a constant current source can readily be converted, provided the supply has remote programming capability.

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