PCI Express System Architecture

Transmitter Driver Characteristics

General

Table 12-1 on this page lists the transmitter driver characteristics.

Table 12-1. Output Driver Characteristics

Item	Max.	Min.	Units	Notes
UI	400.12	399.88	ps	Unit Interval = the bit time. 400 ps nominal.
TTX-EYE		0.7	UI	Minimum eye width from which maximum jitter can be derived. JT = 1 - TTX-EYE
JT	0.3		UI	Maximum jitter spec shown in Figure 12-11 on page 473.
TTX-RISE TTX-FALL		0.125	UI	Rise and Fall time for differential signal measured at the 20%/80% voltage point.
VTX-DIFFp-p	1200	800	mV	Peak-to-peak differential voltage.
VTX-DIFFp	600	400	mV	Half of VTX-DIFFp-p.
VTX-DC-CM	3.6	0	V	DC common mode voltage.
VTX-DEEMPH-DIFFp-p-MIN	566	505	mV	Range of minimum differential peak-to-peak voltages for de-emphasized bits. This is a 3dB - 4dB de-emphasis ...