TMDS341 Datasheet, PDF (13/25 Pages) Texas Instruments – 3-TO-1 DVI/HDMI SWITCH

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PARAMETER MEASUREMENT INFORMATION (continued)
TMDS341
SLLS660A – AUGUST 2005 – REVISED OCTOBER 2005
Data +
Data −
Video Patterm
Generator
1000 mVpp
Differential
Clk+
Clk−
Coax
SMA
Coax
SMA
Coax
SMA
Coax
SMA
RX
+
M
OUT
U
0dB
EQ
X
5m 28AWG
HDMI Cable
TMDS341
RX
+
M
OUT
U
0dB
EQ
X
<2” 50 Ω
SMA
Transmission Line
<2” 50 Ω
SMA
Transmission Line
Coax
Coax
<2” 50 Ω
SMA
Transmission Line
<2” 50 Ω
SMA
Transmission Line
Coax
Coax
AVcc
R_T R_T
Jitter Test
Instrument
AVcc
R_T R_T
Jitter Test
Instrument
TP1
TP2
TP3
A. All jitters are measured in BER of 10^-12
B. The residual jitter reflects the total jitter measured at the TMDS341 output, TP3, subtract the total jitter from the signal
generator, TP1
Figure 8. Jitter Test Circuit
Figure 9 shows the frequency loss response from a 5m 28AWG HDMI cable and a 5m 28AWG DVI cable. The
TMDS341 built-in passive input equalizer compensates for ISI. For an 8-dB loss HDMI cable, the TMDS341
typically reduces jitter by 60 ps from the device input to the device output.
TMDS341 input equalization gain vs. 5m DVI/HDMI cable response
0
Inversed TMDS341 EQ Gain
−2
−4
−6
28 AWG 5m HDMI Cable
−8
−10
−12
28 AWG 5m DVI Cable
−14
−16
−18
0
200 400 600 800 1000 1200 1400 1600 1800 2000
f − Frequency − MHz
Figure 9. S-Parameter Plots of 5-m DVI and HDMI Cables
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