Stanford Research Systems DS335, User Manual

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4-16 Calibration
DS335 Synthesized Function Generator
DS335 CALBYTES
Number Name Meaning
0 OSC_FREQ Sets 10 MHz clock. 0 to 4095. Nom:2048
1 SINE_AMP L.F. Sine amplitude. 29,000 to 36,000. Nom:2^15.
2 SQ_AMP L.F. Square amplitude. 29,000 to 36,000. Nom:2^15.
3 TRI_AMP L.F. Triangle amplitude. 29,000 to 36,000. Nom:2^15.
4 RAMP_AMP L.F. Ramp amplitude. 29,000 to 36,000. Nom:2^15.
5 NOISE_AMP L.F. Noise amplitude. 29,000 to 36,000. Nom:2^15.
6 OFFS_GAIN Adjusts gain for output offsets. 29k-36k Nom:2^15
7 SW_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
8 0dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
9 2dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
10 4dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
11 6dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
12 8dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
13 10dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
14 12dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
15 14dB_OFF +/-127. Nom:0. Value added to 12 bit Offset DAC.
Pre-attenuator gain calibration values. These values are linear in the measured gain for the pre-attenuator.
16 PRE_0dB Always set to 2^16-1 (65535). The reference gain.
17 PRE_2dB +/- 5% from nominal value of 52057.
18 PRE_4dB +/- 5% from nominal value of 41350.
19 PRE_6dB +/- 5% from nominal value of 32845.
20 PRE_8dB +/- 5% from nominal value of 26090.
21 PRE_10dB +/- 5% from nominal value of 20724.
22 PRE_12dB +/- 5% from nominal value of 16461.
23 PRE_14dB +/- 5% from nominal value of 13076.
Post-attenuator gain calibration values. These values are linear in the measured gain for the post-amplifier
attenuator. There are two of these tables corresponding to the measured gains in the 50 Ohm, and High-
Impedance load conditions. These tables compensate for attenuator errors, finite amplifier output resistance,
internal 50 Ohm resistor tolerances, and reflects the fact that the output amplitude of high-impedance loads is
twice that of the 50 Ohm cases.
High Impedance table goes first, as its first entry is the reference gain for all other measurements:
24 HI_0dB Fixed at 2^16-1 (65535). Reference gain level.
25 HI_2dB +/- 5% from nominal value of 52057.
26 HI_4dB +/- 5% from nominal value of 41350.
27 HI_6dB +/- 5% from nominal value of 32845.
28 HI_8dB +/- 5% from nominal value of 26090.
29 HI_10dB +/- 5% from nominal value of 20724.
30 HI_12dB +/- 5% from nominal value of 16461.
31 HI_14dB +/- 5% from nominal value of 13076.
32 HI_16dB +/- 5% from nominal value of 10386.
33 HI_18dB +/- 5% from nominal value of 8250.
34 HI_20dB +/- 5% from nominal value of 6553.
35 HI_22dB +/- 5% from nominal value of 5205.
36 HI_24dB +/- 5% from nominal value of 4135.
37 HI_26dB +/- 5% from nominal value of 3284.
38 HI_28dB +/- 5% from nominal value of 2609.
39 HI_30dB +/- 5% from nominal value of 2072.