adn8102 Analog Devices, Inc., adn8102 Datasheet - Page 23

• Manufacturer Part Number: adn8102
• Description: 3.75 Gbps Quad Bidirectional Cx4 Equalizer
• Manufacturer: Analog Devices, Inc.

High Current Setting and Output Level Shift
In low voltage applications, users must pay careful attention to
both the differential and common-mode signal levels (see Figure 41
and Table 14 and Table 15. Failure to understand the implications
of signal level and choice of ac or dc coupling almost certainly leads
to transistor saturation and poor transmitter performance.
TxHeadroom
The TxHeadroom register (Register 0x23) allows configuration
of the individual transmitters for extra headroom at the output
for high current applications. The bits in this register are active
high (default) and are one per output (see Table 17). Setting a
bit high puts the respective transmitter in a configuration for
extra headroom and setting a bit low does not provide extra
headroom. The TxHeadroom bits should only be set high when
V
CC
exceeds the value listed in Table 14 for a given output swing.
Rev. A | Page 23 of 32
V
OD
ΔV
Figure 41. Simplified Output Voltage Levels Diagram
OCM
p-p = 2 × V
V
OD
OD
V
V
OCM
V
H
L
VTTO
VEE
ADN8102