
IDT SerDes
PES32NT24xG2 User Manual
8 - 7
January 30, 2013
Notes
Table 8.6 shows a number of possible settings for the drive and de-emphasis in Gen 1 mode
1
. These
can be used as guidance when adjusting the SerDes transmit drive swing. The default setting is highlighted.
Note that in Gen 1 mode, de-emphasis is ideally -3.5 dB with +/- 0.5 dB error (refer to Section 4.3.3.5 of the
PCI Express Base 2.1 Specification). The settings listed in the table ensure that the de-emphasis is kept
within the allowable range.
Table 8.7 shows a number of possible settings for the drive and de-emphasis in Gen 2 mode with -3.5
dB de-emphasis
2
. The default setting is highlighted.
1.
Table values are based on simulations using the Snowbush SerDes HSPICE model and device package s-
parameters. Values are sampled at the device pins. The simulation assumes typical conditions, with VddPEA =
VddPETA = 1.0V, VddPEHA = 2.5V, and TX_AMPBOOST = 0x0. The values in the tables may differ from those of
post-silicon characterization. Please refer to the device data sheet for post-silicon device characterization data.
Transmit Levels
Settings of Relevant Fields in the
S[x]TXLCTL0 & S[x]TXLCTL1 Registers
Drive
Level
(mV)
De-empha-
sis (dB)
De-empha-
sized Drive
Level (mV)
TDVL_FS3DBG1
CDC_FS3DBG1
FDC_FS3DBG1
TX_SLEW_G1
887
-3.5
590
0x13
0x3
0x2
0x1
872
-3.6
576
0x12
0x3
0x2
0x1
840
-3.5
558
0x11
0x3
0x2
0x1
808
-3.5
541
0x10
0x3
0x2
0x1
776
-3.4
523
0xF
0x3
0x1
0x1
744
-3.4
505
0xE
0x3
0x1
0x1
712
-3.3
487
0xD
0x3
0x1
0x1
674
-3.4
457
0xC
0x3
0x1
0x1
635
-3.5
427
0xB
0x3
0x1
0x1
597
-3.6
397
0xA
0x3
0x1
0x1
558
-3.7
366
0x9
0x3
0x1
0x1
512
-3.6
336
0x8
0x3
0x1
0x1
465
-3.6
306
0x7
0x3
0x0
0x1
419
-3.6
275
0x6
0x3
0x0
0x1
372
-3.6
245
0x5
0x2
0x3
0x1
324
-3.8
211
0x4
0x2
0x3
0x1
276
-4.0
177
0x3
0x2
0x2
0x1
Table 8.6 SerDes Transmit Driver Settings in Gen 1 Mode with -3.5 dB de-emphasis
2.
Table values are based on simulations using the Snowbush SerDes HSPICE model and device package s-
parameters. Values are sampled at the device pins. The simulation assumes typical conditions, with VddPEA =
VddPETA = 1.0V, VddPEHA = 2.5V, and TX_AMPBOOST = 0x0. The values in the tables may differ from those of
post-silicon characterization. Please refer to the device data sheet for post-silicon device characterization data.
Summary of Contents for PCI Express 89HPES32NT24xG2
Page 20: ...IDT Table of Contents PES32NT24xG2 User Manual x January 30 2013 Notes...
Page 24: ...IDT List of Tables PES32NT24xG2 User Manual xiv January 30 2013 Notes...
Page 28: ...IDT List of Figures PES32NT24xG2 User Manual xviii January 30 2013 Notes...
Page 56: ...IDT PES32NT24xG2 Device Overview PES32NT24xG2 User Manual 1 20 January 30 2013 Notes...
Page 100: ...IDT Switch Core PES32NT24xG2 User Manual 4 22 January 30 2013 Notes...
Page 128: ...IDT Failover PES32NT24xG2 User Manual 6 4 January 30 2013 Notes...
Page 148: ...IDT Link Operation PES32NT24xG2 User Manual 7 20 January 30 2013 Notes...
Page 164: ...IDT SerDes PES32NT24xG2 User Manual 8 16 January 30 2013 Notes...
Page 170: ...IDT Power Management PES32NT24xG2 User Manual 9 6 January 30 2013 Notes...
Page 196: ...IDT Transparent Switch Operation PES32NT24xG2 User Manual 10 26 January 30 2013 Notes...
Page 244: ...IDT SMBus Interfaces PES32NT24xG2 User Manual 12 40 January 30 2013 Notes...
Page 247: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 3 January 30 2013 Notes...
Page 248: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 4 January 30 2013 Notes...
Page 330: ...IDT Switch Events PES32NT24xG2 User Manual 16 6 January 30 2013 Notes...
Page 342: ...IDT Multicast PES32NT24xG2 User Manual 17 12 January 30 2013 Notes...
Page 344: ...IDT Temperature Sensor PES32NT24xG2 User Manual 18 2 January 30 2013 Notes...
Page 384: ...IDT Register Organization PES32NT24xG2 User Manual 19 40 January 30 2013...
Page 492: ...IDT Proprietary Port Specific Registers PES32NT24xG2 User Manual 21 44 January 30 2013 Notes...
Page 588: ...IDT NT Endpoint Registers PES32NT24xG2 User Manual 22 96 January 30 2013 Notes...
Page 710: ...IDT JTAG Boundary Scan PES32NT24xG2 User Manual 25 12 January 30 2013 Notes...
Page 743: ...IDT Usage Models PES32NT24xG2 User Manual 26 33 January 30 2013 Notes...
Page 744: ...IDT Usage Models PES32NT24xG2 User Manual 26 34 January 30 2013 Notes...