Agilent Technologies 90B manual Ideal Remote Programming Characteristics

Figure 59. Ideal Remote Programming Characteristics

As Figure 60 indicates, all power supplies deviate somewhat from the ideal. The application of a short-circuit across the programming terminals results in an output voltage which is slightly different from zero (typically between +20 millivolts and -50 millivolts). While the linearity of the programming characteristic is nearly perfect, the overall slope may differ from the value predicted by the programming coefficient by from 1% to 5%. The fact that this slope is extremely linear can be utilized in improving the absolute accuracy in programming a supply, since by pinpointing two points on this straight line segment, all other points are thereby determined. The two points which are the easiest (and best) to fix are zero and maximum output voltage. If these two points are successfully relocated, the graph of Figure 60 can be changed into one closely approximating that shown in Figure 59, which is the characteristic of an ideal supply having perfect programming accuracy.

Figure 60. Practical Remote Programming Characteristic

Regardless of the programming coefficient, an ideal programmable supply having absolute programming

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