SC5 Signal Conversion Performance Measurements
54
Analog outputs noise performance measurements
All measurements of the analog outputs, if not otherwise specified, were performed with hrDAC™ switched off.
Spectral noise
The noise spectrum of the analog outputs is measured with AO1 conneced to a battery-powered Stanford Research
Systems SR560 low-noise differential preamplifier set to gain 1000, and the spectrum is recorded using a National
Instruments 4071 PXI digital multimeter operated in digitizer mode. The pictures below show the noise spectrum for
the range of 1 kHz (0 V and +9 V DC output). The low frequency range up to 50 Hz and the high frequency range up
to 300 kHz is shown in separate plots below. Note that line voltage frequency and harmonic components strongly
depend on the measurement set-up.
The following settings have been used for the measurement:
DMM
Measured output: AO1 Mode of operation: Digitizer, DC volts
Output amplitude: 0 V and 9 V Range: 100 mV
Resolution: 22 bit
FFT resolution 20’000 points
Figure 34: Spectral noise of the analog outputs up to 1 kHz. The left picture is for 0 V output voltage, the right picture for
+9 V output voltage.
Figure 35: Spectral noise of the analog outputs up to 300 kHz (left) and 50 Hz (right) at 0 V output.
0 100 200 300 400 500 600 700 800 900 1000
Frequency [Hz]
Spectral noise [nV/ Hz]
1000
100
10
Output range: ±10 V
Output voltage: 0 V
0 100 200 300 400 500 600 700 800 900 1000
Frequency [Hz]
Spectral noise [nV/ Hz]
Output range: ±10 V
Output voltage: +9 V
1000
100
10
Output range: ±10 V
Output voltage: +9 V
0 50 100 150 200 250 300
Frequency [kHz]
Spectral noise [nV/ Hz]
100
10
1
Output range: ±10 V
Output voltage: 0 V
To Next Page
Loading...
Need help?
General