05 | Keysight | N5399C, N5399D HDMI Electrical Performance Validation and Compliance Software - Data Sheet
New HDMI Transmitter Test Requirements for HDMI 2.0
While many of the tests remain similar for HDMI 2.0, there are
many complex mathematical processes that are now required
for the test processing on the oscilloscope for the data rates
above 3.4 Gbs. These ‘complex mathematical processes’ amount
to filtering acquired data using transfer functions to obtain the
required view. Examples of such functions are finite impulse
response filters (FIRs) that can be convolved with acquisitions to
accomplish de-embedding the fixture and embedding a worst-
case cable. In the figure below, we have an idealized HDMI link
with HDMI transmitter, sink and cable between them.
To validate a transmitter (at test point 1), we must access the
signals of the transmitter with a test point adapter and analyze
with an oscilloscope. This is shown in the middle portion of the
figure. The HDMI 2.0 required processing functions are depicted
below the oscilloscope block. These functions include: fixture
de-embedding for removing the effects of the fixture; impressing
a cable model that is considered a worst-case acceptable cable
in an HDMI system (loss vs. frequency); adding worst-case
skew to either side of the differential pair (one signal at a time);
and modeling the minimum equalization an HDMI receiver will
have (the HDMI reference equalizer). The HDMI EPVC software
generates all of these transfer functions and enables any
combination of them. Further, the implementation is performed
automatically in hardware by real-time convolution subsequent
to the acquisition. The result is the fastest waveform processing
available for HDMI 2.0 electrical testing.
HDMI
HDMI
sink
transmitter
TP1
TP2
Oscilloscope acquisition
and transfer function
application
Test point adapter
TP1
TP1’
TP2
Acquisition
Fixture
De-embedding
TP2Eq
Worst case
cable
embedding
Worst case
skew
Reference
equalization
modeled
Measurement
Figure 4. Test point 1 acquisition with test point adaptor with subsequent mathematical processing
functions available.
KEYSIGHT [ Keysight Technologies ]
