Agilent Technologies E3615A, E3614A, E3617A, E3616A PARDRipple and Noise, Pardrms Measurement

Figure A-5. Load Transient Response Time Waveform

PARD(Ripple and Noise)

Definition: PARD is the Periodic and Random Deviation of the dc output voltage from its average value, over a specified bandwidth and with all other parameters maintained constant. Constant voltage PARD is measured in the root-mean- square(rms) or peak-to-peak(pp) values over a 20 Hz to 20 MHz bandwidth. Fluctuations below the lower frequency limit are treated as drift.

PARD(RMS) Measurement

The rms measurement is not an ideal representation of the noise, since fairly high output noise spikes of short duration could be present in the ripple and not appreciably increase the rms value.

Test Parameter:

Measured Variable: Output Voltage(rms)

Expected Results: Less than 200 μV rms

Test Procedure:

a.Connect the test equipment as shown in Figure A-6.

b.Turn the supply's power on and turn CURRENT con- trol fully clockwise.

c.Turn up output voltage to the full rated value. Check that the supply's CV indicator remains lighted. Reduce VOLTAGE control if not lighted.

d.Check that the rms noise voltage at the true rms volt- meter is less than 200BμV.

Figure A-6. CV PARD RMS Measurement Test Setup

PARD(Peak-to-Peak) Measurement

The peak-to-peak measurement is particularly important for applications where noise spikes could be detrimental to a sensitive load, such as logic circuitry.

Test Parameter:

Measured Variable: Output voltage(peak-to-peak)

Expected Results: Less than 1 mV p-p (20 Hz-20 MHz)

Test Procedure:

A-5