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May 7, 2009
IDT 89HPES8T5A Data Sheet
DC Electrical Characteristics
Values based on systems running at recommended supply voltages, as shown in
Table 13.Note: See
Table 8, Pin Characteristics, for a complete I/O listing.
I/O Type Parameter
Description
Min1
Unit
Conditions
Serial Link
PCIe Transmit
VTX-DIFFp-p
Differential peak-to-peak output voltage
800
1200
mV
VTX-DE-RATIO
De-emphasized differential output voltage
-3
-4
dB
VTX-DC-CM
DC Common mode voltage
-0.1
1
3.7
V
VTX-CM-ACP
RMS AC peak common mode output volt-
age
20
mV
VTX-CM-DC-
active-idle-delta
Abs delta of DC common mode voltage
between L0 and idle
100
mV
VTX-CM-DC-line-
delta
Abs delta of DC common mode voltage
between D+ and D-
25
mV
VTX-Idle-DiffP
Electrical idle diff peak output
20
mV
VTX-RCV-Detect Voltage change during receiver detection
600
mV
RLTX-DIFF
Transmitter Differential Return loss
12
dB
RLTX-CM
Transmitter Common Mode Return loss
6
dB
ZTX-DEFF-DC
DC Differential TX impedance
80
100
120
Ω
ZOSE
Single ended TX Impedance
40
50
60
Ω
Transmitter Eye
Diagram
TX Eye Height (De-emphasized bits)
505
650
mV
Transmitter Eye
Diagram
TX Eye Height (Transition bits)
800
950
mV
PCIe Receive
VRX-DIFFp-p
Differential input voltage (peak-to-peak)
175
1200
mV
VRX-CM-AC
Receiver common-mode voltage for AC
coupling
150
mV
RLRX-DIFF
Receiver Differential Return Loss
15
dB
RLRX-CM
Receiver Common Mode Return Loss
6
dB
ZRX-DIFF-DC
Differential input impedance (DC)
80
100
120
Ω
ZRX-COMM-DC
Single-ended input impedance
40
50
60
Ω
ZRX-COMM-HIGH-
Z-DC
Powered down input common mode
impedance (DC)
200k
350k
Ω
VRX-IDLE-DET-
DIFFp-p
Electrical idle detect threshold
65
175
mV
PCIe REFCLK
CIN
Input Capacitance
1.5
—
pF
Table 17 DC Electrical Characteristics (Part 1 of 2)