Keysight 34450A Guia Del Usuario página 109

Traditionally, digital multimeters include a crest factor derating table that applies
at all frequencies. The measurement algorithm used in the 34450A multimeter is
not inherently sensitive to crest factor, so no such derating is necessary. With this
multimeter, as discussed in the previous section, the focal issue is high-frequency
signal content which exceeds the multimeter's bandwidth.
For periodic signals, the combination of crest factor and repetition rate can
suggest the amount of high-frequency content and associated measurement
error. The first zero crossing of a simple pulse occurs at
This gives an immediate impression of the high-frequency content by identifying
where this crossing occurs as a function of crest factor:
Table 3-3
of input pulse frequency:
Table 3-3 Typical errors for various pulse waveforms as a function of input pulse frequency
prf
200
1000
2000
5000
10000
20000
50000
100000
Keysight 34450A User's Guide
below shows the typical errors for various pulse waveforms as a function
Typical error for square wave, triangular wave, and pulse trains of CF=3, 5, or 10
Square wave Triangle wave
–0.02% 0.00%
–0.07% 0.00%
–
0.00%
0.14%
–
0.34% 0.00%
–
0.68% 0.00%
–
0.00%
1.28%
– –
3.41% 0.04%
– –
5.10% 0.12%
Measurement Tutorial
CF=3 CF=5
–0.04% –0.09%
–0.18% –0.44%
–0.34% –0.88%
– –
0.84% 2.29%
– –
1.75% 4.94%
– –
3.07% 8.20%
– –
6.75% 32.0%
– –
21.8% 50.6%
3
CF=10
–0.34%
–1.71%
–3.52%
–
8.34%
–
26.00%
–
45.70%
–
65.30%
–
75.40%
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