APPLy Subsystem
Parameter
Typical Return
<
frequency
> in bits/s, default 1000
(none)
<
amplitude
> Desired output amplitude in Vpp, Vrms or dBm, as specified by
.1
mVpp to 10 Vpp into 50 Ω, or twice that into an open circuit.Default 100 mVpp into 50 Ω
<
offset
> is the DC offset voltage (default 0), from ±5 VDC into 50 Ω, or from ±10 VDC into an
open circuit.
Output pseudo-random bit sequence bounded by 3 Vpp, with -2.5 V offset:
APPL:PRBS 5 KHZ, 3.0 V, -2.5 V
Frequency
l
PRBS is generated by a Maximum Length Sequence (MLS) generator (Linear Feedback Shift Register) which may
be configured to several standard configurations. Default is PN7 at 1000 bits/second.
l
A PRBS waveform using polynomial PN
x
is generated by a shift register of
x
bits, and the output waveform begins
with
x
sample periods of high output. Sample period is the reciprocal of the sample rate (
),
and the channel's
Sync
pulse indicates the waveform's start. For example, if the PRBS uses PN23 with sample
rate 500 Hz, the output begins with 46 ms of high output (23 x 2 ms).
l
Unlike the APPLy:NOISe function, the APPLy:PRBS function operates with the
Sync
output enabled. The
Sync
function indicates the beginning of the Pseudo-random function sequence.
Offset Voltage
l
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.
l
Limits Due to Output Termination: The offset range depends on the output termination setting. For example, if
you set offset to 100 mVDC and then change output termination from 50 Ω to "high impedance," the offset volt-
age displayed on the front panel doubles to 200 mVDC (no error is generated). If you change from "high imped-
ance" to 50 Ω, the displayed offset voltage will be halved. See
for details.
[SOURce[1|2]:]APPLy:PULSe [{<
frequency
>|MIN|MAX|DEF}
[,{<
amplitude
>|MIN|MAX|DEF} [,{<
offset
>|MIN|MAX|DEF}]]]
Outputs a pulse wave with the specified frequency, amplitude, and DC offset. In addition,
performs the following
operations:
l
Preserves either the current pulse width setting (FUNCtion:PULSe:WIDTh) or the current pulse duty cycle setting
(FUNCtion:PULSe:DCYCle).
l
Preserves the current transition time setting (FUNCtion:PULSe:TRANsition[:BOTH]).
l
May cause instrument to override the pulse width or edge time setting to comply with the specified frequency or
period (FUNCtion:PULSe:PERiod).
Agilent 33500 Series Operating and Service Guide
167
