Agilent Technologies E3631A Normal Mode Voltage Noise (CV Ripple and Noise)

Chapter 3 Calibration Procedures
Constant Voltage (CV) Verifications
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3
Normal Mode Voltage Noise (CV Ripple and Noise)
The normal mode voltage noise is in the form of ripple related to the line
frequency plus some random noise. The normal mode voltage noise is specified
as the rms or peak-to-peak output voltage in a frequency range from 20 Hz to
20 MHz.
1Turn off the power supply and connect the output to be tested as shown in Figure
3-1 to an oscilloscope (ac coupled) between (+) and (-) terminals. Set the
oscilloscope to AC mode and bandwidth limit to 20 MHz. Con nect a resistive
load (1.2 for +6V supply and 25 for ±25V supplies) as shown in Figure 3-1 (see
Table 3-2).
2Turn on the power supply and select the output to be tested using the meter
and adjust selection key on the front panel. Enable the outputs and set the
display to the limit mode. When the display is in the limit mode, program the
current of the selected output to the maximum programmable value and the
voltage to the full-scale value (see Table 3-2).
3Check that the front panel CV annunciator remains lit. If not lit, adjust the load
down slightly.
4Note that the waveform on the oscilloscope does not exceed the peak-to-peak
limit of 2 mV for each of the three outputs.
5Disconnect the oscilloscope and connect an AC rms voltmeter in its place. The
rms voltage reading does not exceed the rms limit of 0.35 mV for each of the
three outputs.
6Repeat steps (1) through (5) for the remaining outputs.