VOLTage Subsystem Introduction
Parameter
Typical Return
1 mVpp to 10 Vpp into 50 Ω, default 100 mVpp
+5.000000000
Set output amplitude to 5 Vpp:
VOLT 5 Vpp
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The relationship between offset voltage and output amplitude is shown below. Vmax is the maximum peak voltage
for the selected output termination (5 V for a 50 Ω load or 10 V for a high-impedance load).
|Voffset| < Vmax - Vpp/2
If the specified offset voltage is not valid, the instrument will adjust it to the maximum DC voltage allowed with the
specified amplitude. From the remote interface, a "Data out of range" error will also be generated.
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Differences between remote and front panel operation:
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Remote Interface:
Setting amplitude from the remote interface can change the offset in order to achieve the
desired amplitude. The instrument will generate either a "Data out of range" or "Settings conflict" error. If the
specified offset voltage is not valid, the instrument adjusts it to the maximum allowed with the specified ampli-
tude.
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Front Panel:
Setting amplitude from the front panel will not change the offset setting. If the specified ampli-
tude is not valid, the instrument clips it to the maximum amplitude allowed with the current offset and gen-
erates a "Data out of range" error.
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Limits Due to Output Termination:
If the amplitude is 10 Vpp and you change the output termination setting from
50 Ω to "high impedance" (
), the displayed amplitude doubles to 20 Vpp. Changing from
"high impedance" to 50 Ω halves the displayed amplitude. The output termination setting does not affect the
actual output voltage; it only changes the values displayed and queried from the remote interface. Actual output
voltage depends on the connected load.
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Limits due to Output Coupling:
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Differences between remote and front panel operation:
If two channels are coupled, both channels' amplitude
limitations will be checked before a change in amplitude is executed. If a change in output amplitude would
exceed a LIMIT for either channel, or exceed the instrument's output specifications for either channel:
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Remote interface:
The instrument will first adjust the offset, then if necessary, the amplitude of that
channel to comply with the voltage limits or specification. The instrument will generate either a "Data out
of range" or "Settings conflict" error.
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Front panel:
The instrument will clip the amplitude value to the maximum value with the current offset
setting. A "Data out of range" error will be generated.
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Specifying Voltage Units:
You can set the output amplitude in Vpp, Vrms, or dBm by specifying the units as part of
the VOLTage command VOLT 3.0 VRMS.
Use
to specify output units for all subsequent commands.
You cannot specify output amplitude in dBm if output termination is set to high impedance.The units are auto-
matically converted to Vpp.
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Limits Due to Units Selection:
Amplitude limits are sometimes determined by the output units selected. This may
occur when the units are Vrms or dBm due to the differences in various functions' crest factors. For example, if you
change a 5 Vrms square wave (into 50 Ω) to a sine wave, the instrument will adjust the amplitude to 3.536 Vrms
(the upper limit for sine in Vrms). The remote interface will also generate a "Settings conflict" error.
Agilent 33500 Series Operating and Service Guide
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