![Keysight U4421A Скачать руководство пользователя страница 17](http://html1.mh-extra.com/html/keysight/u4421a/u4421a_hardware-and-probing-manual_1961143017.webp)
Keysight U4421A MIPI D-PHY Analyzer and Exerciser Hardware and Probing Guide
17
Setting up a Stimulus Probe Configuration for U4421A Module
2
Supplying External Reference Clock to the U4421A Module
You can connect the
Refp
and
Refn
coaxial cables of the stimulus probe to accept the external
reference clock input signals.
The following table lists some important points that you should consider while making connections
for supplying the external reference clock to the U4421A module.
NOTE
You can set the
Target VDD
for the
Vsen
signal in the Keysight Logic And
Protocol Analyzer GUI. Setting this value ensures that the U4421A module
sends D-PHY signals to the DUT if the
Vsen
signal is above this value divided by
two. If the
Vsen
signal is below the set Target VDD divided by two, the module
will tri-state all the D-Phy signals. Refer to the
U4421A MIPI D-PHY Protocol
Analyzer and Exerciser Online Help
to know how to set and enable/disable the
Target VDD.
Supplying the Refp and Refn
signals to the U4421A module
Use either of the following two methods:
• From a piece of test equipment such as a signal generator
• By probing a signal on the DUT - Place 1K Ohm isolation resistor in series with the Ref[pn]
signals.
Refp and Refn input signals
specifications
•
This input can be provided:
• single-ended - Ensure that the unused input from the single-ended source is terminated
with 50 Ohms to ground.
• differentially
•
Minimum input signal amplitude
• typically 20mV if supplied directly
• 400mV if supplied by probing a signal
•
Maximum input signal amplitude - 2V pp
•
Signals are AC coupled and terminated with 50 Ohms.
•
The supplied signal should have a 50% duty cycle. Since this signal is AC coupled, the DC
common mode of the supplied signal does not affect the signal detection but must be kept to
a voltage of less than 10V.
Reference Clock Frequency
1/10 the bit rate for bit rates < = 700mbps
1/20 the bit rate for rates > 700mbps
NOTE
Once you have connected the probe cables for supplying the external reference clock to the
U4421A module, you also need to configure the U4421A module to use the external
reference clock. You do this configuration by specifying the Clock Source as External in the
U4421A Setup dialog box in the Keysight Logic and Protocol Analyzer GUI. To know more,
refer to the
U4421A Online Help
.
Содержание U4421A
Страница 1: ...Keysight U4421A MIPI D PHY Protocol Analyzer and Exerciser Hardware and Probing Guide...
Страница 6: ...6 Keysight U4421A MIPI D PHY Analyzer and Exerciser Hardware and Probing Guide...
Страница 48: ...Index 48 Keysight U4421A MIPI D PHY Analyzer and Exerciser Hardware and Probing Guide...