Power Analysis
197
19.10
PSRR
The power supply rejection ratio (PSRR) test is used to determine how the regulator suppresses ripple noise in different
frequency ranges. The oscilloscope controls the arbitrary waveform/function generator to output a sweep signal, which
is used to introduce ripple into the DC voltage transmitted to the voltage regulator.
Measure the AC RMS ratio of input to output, and plot the relationship between the ratio and frequency. The background
noise of the oscilloscope is higher than that of the network analyzer, and the sensitivity is lower than that of the network
analyzer, so the PSRR measured by the oscilloscope is difficult to exceed -60 dB.
The PSRR test is generally acceptable for sampling the overall PSRR behavior of the power supply under test.
19.10.1
PSRR Configuration
The configuration of PSRR is the same as that of the bode plot, see the chapter "
for details.
19.10.2
PSRR Amplitude
1.
Touch
Amplitude
to display the signal menu shown in figure
2.
Touch
Scale
and turn the
Universal Knob
or use the virtual
numeric keypad to set the scale value.
–
The range is .10dB to 20 dB.
3.
Touch
Ref Level
and turn the
Universal Knob
or use the virtual
numeric keypad to set the reference value.
–
The range is -200 dB to 200 dB
4.
Touch
Mode
to toggle between
Vout/Vin
and
Vout
mode.
5.
Touch
Axis Type
to toggle the axis type between
Linear
and
Logarithmic
.
Figure 19.24
PSRR
Amplitude Menu
Содержание 2560B Series
Страница 1: ......
Страница 51: ...Digital Channels 51 Figure 8 9 Digital Bus...
Страница 127: ...Serial Trigger and Decode 127 Figure 10 63 Manchester Bus...
Страница 168: ...Reference Waveform 168 Figure 14 1 Recall REFB...
Страница 210: ...Save Recall 210 Figure 22 4 Save As...