Chapter 7 Tutorial

Remote Programming

Remote Programming

During remote programming a constant-voltage regulated power supply is called upon to change its output voltage rapidly. The most important factor limiting the speed of output voltage change is the output capacitor and load resistor.

Figure 7-8. Speed of Response - Programming Up (Full Load)

The equivalent circuit and the nature of the output voltage waveform when the supply is being programmed upward are shown in Figure 7-8. When the new output is programmed, the power supply regulator circuit senses that the output is less than desired and turns on the series regulator to its maximum value IL, the current limit or constant current setting.

This constant current IL charges the output capacitor CO and load resistor RL parallel. The output therefore rises exponentially with a time constant RLCL towards voltage level ILRL , a value higher than the new output voltage being programmed.

When this exponential rise reaches the newly programmed voltage level, the constant voltage amplifier resumes its normal regulating action and holds the output constant. Thus, the rise time can be determined approximately using the formula shown in Figure 7-8.

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Agilent Technologies E3632A manual Tutorial Remote Programming, 152