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Quick Start Guide
6.
Set the output VOD and De-emphasis level.
•
For external pin mode control for the VOD and De-emphasis level:
•
Set ENSMB = 0 (1k
Ω
to GND) by using the SW2 (3-2-1) = (ON-OFF-OFF).
•
SW4 pin1,2 must be set to the OFF positions, so the SMBUS signals are disconnected.
•
Refer to
Table 1
for information on the 3 switch settings for the 4 level input.
Example:
•
Set DEMB[1:0] with SW5 for the B bank of outputs (top 4 outputs of DS125BR800).
•
SW5 (6-5-4), (3-2-1) = (ON-OFF-OFF), (OFF-OFF-ON) = DEMB[1:0] = 0,1 (VOD=1.0V, DE=0 dB).
•
Set DEMA[1:0] with SW3 for the A bank of outputs (bottom 4 outputs of DS125BR800).
•
SW3 (6-5-4), (3-2-1) = (ON-OFF-OFF), (OFF-OFF-ON) = DEMA1:0] = 0,1 (VOD=1.0V, DE=0 dB).
Table 5. DE and VOD Settings available in PIN MODE
Level
EQA/B[1:0]
SW1 - EQB[1:0] or SW8 - EQA[1:0]
GEN1 and GEN2
Inner Amplitude
6
5
4
3
2
1
DE (dB)
(V
PP
)
1
0, 0
ON
OFF
OFF
ON
OFF
OFF
0.8
0
2
0, R
ON
OFF
OFF
OFF
ON
OFF
0.9
0
3
0, F
ON
OFF
OFF
OFF
OFF
OFF
0.6
-3.5
4
0, 1
ON
OFF
OFF
OFF
OFF
ON
1.0
0
5
R, 0
OFF
ON
OFF
ON
OFF
OFF
0.7
-3.5
6
R, R
OFF
ON
OFF
OFF
ON
OFF
0.5
-6
7
R, F
OFF
ON
OFF
OFF
OFF
OFF
1.1
0
8
R, 1
OFF
ON
OFF
OFF
OFF
ON
0.7
-3.5
9
F, 0
OFF
OFF
OFF
ON
OFF
OFF
0.6
-6
10
F, R
OFF
OFF
OFF
OFF
ON
OFF
1.2
0
11
F, F
OFF
OFF
OFF
OFF
OFF
OFF
0.8
-3.5
12
F, 1
OFF
OFF
OFF
OFF
OFF
ON
0.6
-6
13
1, 0
OFF
OFF
ON
ON
OFF
OFF
1.3
0
14
1, R
OFF
OFF
ON
OFF
ON
OFF
0.9
-3.5
15
1, F
OFF
OFF
ON
OFF
OFF
OFF
0.7
-6
16
1, 1
OFF
OFF
ON
OFF
OFF
ON
0.5
-9
NOTE:
The De-Emphasis levels are also available in SAS-3 / GEN-3 mode when MODE = 1
9
SNLU122 – November 2012
DS125BR800EVM Evaluation Kit
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