Tsi721 Datasheet 43 April 4, 2016
Integrated Device Technology
3.7.4 Level I Long Run Transmitter Specifications
1. For all Load Types: R_Rdin = 100 Ohm +/- 20 Ohm.
2. Load Type 0 with min. T_Vdiff, AC-coupling or floating load.
3. It is suggested that T_SCC22 be -6 dB to be compatible with Level II transmitter requirements.
4. It is suggested that T_Ncm be limited to 5% of T_Vdiff to be compatible with Level II transmitter requirements.
For each baud rate at which the LP-Serial transmitter is specified to operate, the output eye pattern of the transmitter falls
entirely within the unshaded portion of the Transmitter Output Compliance Mask displayed in Figure 7 when measured at the
output pins of the device and the device is driving a 100 Ohm + 5% differential resistive load. The specification allows the
output eye pattern of a LP-Serial transmitter that implements pre-emphasis (to equalize the link and reduce inter-symbol
interference) to only comply with the Transmitter Output Compliance Mask when pre-emphasis is disabled or minimized.
Table 21: Level I Long Run Transmitter AC Timing Specifications
Characteristics Symbol Reference Min Typ Max Units
Baud Rate T_Baud Section 9.4.2.2 1.25 - 3.125 Gbps
Absolute Output Voltage V
O
Section 9.4.2.3 -0.40 - 2.30 Volts
Output Differential Voltage
(into floating load Rload = 100 Ohm)
T_Vdiff Section 9.4.2.3 800 - 1600 mVppd
Differential Resistance T_Rd Section 9.4.1.5 80 100 120 Ohm
Recommended output rise and fall
times
(20% to 80%)
T_tr, T_tf - 60 - - ps
Differential Output Return Loss
(T_baud/10 <
f < T_baud/2)
T_SDD22 Section 9.4.1.6 - - - dB
Differential Output Return Loss
(T_baud/10 <
f < T_baud/2)
-- - dB
Common Mode Return Loss
(625 MHz <
f < T_baud)
T_TCC22 Section 9.4.1.6 - - Note 3 dB
Transmitter Common Mode Noise
1
T_Ncm - - Note 4 mVppd
Output Common Mode Voltage T_Vcm Load Type 0
2
0- 2.1 V
Multiple output skew, N <
4S
MO
---1000ps
Multiple output skew, N > 4 S
MO
- - - 2UI + 1000 ps
Unit Interval UI - 80 - 800 ps
