Texas Instruments PCIE16X-800EVK, Руководство пользователя

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8 R ,1 OFF
ON
OFF OFF OFF
ON
18.5
9 F ,0 OFF OFF OFF
ON
OFF OFF 18.0
10 F, R OFF OFF OFF OFF
ON
OFF 22.0
11 F, F OFF OFF OFF OFF OFF OFF 24.4
12 F, 1 OFF OFF OFF OFF OFF
ON
25.8
13 1, 0 OFF OFF
ON ON
OFF OFF 27.4
14 1, R OFF OFF
ON
OFF
ON
OFF 29.0
15 1, F OFF OFF
ON
OFF OFF OFF 31.4
16 1, 1 OFF OFF
ON
OFF OFF
ON
32.7
6. Set the output VOD and De-emphasis level.
For external pin mode control for the VOD and De-emphasis level (Gen1&2 only):
Set ENSMB = 0 (1kohm 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 2 right outputs of DS80PCI800).
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 2 right outputs of DS80PCI800).
SW3 (6-5-4),(3-2-1) = (
ON
-OFF-OFF), (OFF-OFF-
ON
) = DEMA1:0] = 0,1 (VOD=1.0V, DE=0 dB).
The table below is the 16 possible settings of VOD and DE when in pin mode.
In Gen 1/2, the de-emphasis level can be set with the DEMx[1:0] pins, but is not available in Gen 3.
Level DEMA/B[1:0]
SW5 - DEMB[1:0]
SW3 - DEMA[1:0]
GEN1,2
6 5 4 3 2 1 VOD (Vp-p) DE (dB)
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 0.9
‐ 3.5
4 0, 1
ON
OFF OFF OFF OFF
ON
1.0
0
5 R, 0 OFF
ON
OFF
ON
OFF OFF 1.0
‐ 3.5
6 R, R OFF
ON
OFF OFF
ON
OFF 1.0
‐ 6
7 R, F OFF
ON
OFF OFF OFF OFF 1.1
0
8 R ,1 OFF
ON
OFF OFF OFF
ON
1.1
‐ 3.5
9 F ,0 OFF OFF OFF
ON
OFF OFF 1.1
‐ 6
10 F, R OFF OFF OFF OFF
ON
OFF 1.2
0
11 F, F OFF OFF OFF OFF OFF OFF 1.2
‐ 3.5
12 F, 1 OFF OFF OFF OFF OFF
ON
1.2
‐ 6
13 1, 0 OFF OFF
ON ON
OFF OFF 1.3
0
14 1, R OFF OFF
ON
OFF
ON
OFF 1.3
‐ 3.5
15 1, F OFF OFF
ON
OFF OFF OFF 1.3
‐ 6
16 1, 1 OFF OFF
ON
OFF OFF
ON
1.3
‐ 9
For SMBUS mode control of the EQ, VOD and De-emphasis level:
Set ENSMB = 1 (1kohm to VIH) by using the SW2 (3-2-1) = (OFF-OFF-
ON)
.
Set SW4 pin1,2 to the ON position so the SMBUS signals are connected.
Set SW3 pin1 thru pin6 switches to the OFF position so they do not connect to the SDA and SCL line.
Set the SW1 and SW5 for the AD[3:0] pins. AD[3:0]=0000 sets device slave address = B0’hex.
Connect SDA, SCL and GND to J17. Please refer to datasheet for register map for EQ, VOD and DEM.