TMDS261B Datasheet, PDF (21/48 Pages) Texas Instruments – TWO-PORT HDMI SWITCH

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AVCC = 3.3 V, R_T = 50 Ω
TMDS261B
SLLS987A – SEPTEMBER 2009 – REVISED JULY 2011
TYPICAL CHARACTERISTICS (continued)
1600
1400
1200
DIFFERENTIAL OUTPUT VOLTAGE
vs
RESISTANCE
VCC = 3.6 V
T_A = 25°C
1000
800
600
VCC = 3.3 V
VCC = 3 V
400
200
0
3
4
5
6
7
VSadj Resistance − kΩ
G008
Figure 23.
(1) The HDMI cable between TTP1 and TTP2 is 0 m (no loss) case. See Figure 15 for the loss profile of the cable.
(2) Eye data is measured using an 8-GHz bandwith oscilloscope (Agilent).
(3) Eye data is taken at TTP4.
(4) AVCC = 3.3 V; VSadj = 4.02 kΩ.
(5) R_T = 50 Ω.
(6) 2 inches = 5,08 cm.
NOTES: Output edge rate default (fastest): input edge rate from the video pattern generator greater than 75 ps (20%–80%).
The input signal from the parallel BERT has pre-emphasis. See Figure 26 for acceptable input pre-emphasis duration
and amplitude.
Pass/fail criterion: output eye at TTP4 should comply with output eye mask (See Figure 25). The input TMDS clock
frequencies tested: 25 MHz, 30.24 MHz, 36 MHz, 54 MHz, 65 MHz, 74.25 MHz, 84.75 MHz, 108 MHz, 135 MHz,
148.5 MHz, 185.625 MHz, 222.75 MHz, 297 MHz.
Parallel
BERT _Data+
800-mVpp, _Data–
1000-mVpp,
1200-mVpp
Differential
Signal
With
Clk+
Preemphasis
Clk–
(3-dB, 120-ps
Duration
Coax
Coax
SMA
SMA
RX
+EQ
OUT
Coax
Coax
HDMI Cable⁽¹⁾
TMDS261B
SMA
SMA
RX
+EQ
OUT
<2-inch⁽⁶⁾ 50-W
Transmission Line
<2-inch⁽⁶⁾ 50-W
Transmission Line
SMA
Coax
SMA
Coax
<2-inch⁽⁶⁾ 50-W
Transmission Line
<2-inch⁽⁶⁾ 50-W
Transmission Line
SMA
Coax
SMA
Coax
AVCC⁽⁴⁾
R_T R_T(5)
Eye Testnnn
AVCC Instrument^{(2, 3)}
R_T R_T
Eye Testnnn
Instrument^{(2, 3)}
TTP1
TTP2
TTP3
TTP4
Figure 24. Input Pre-Emphasis Tolerance-Measurement Setup
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B0331-10
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