1 Features
1• User-configurable adaptive cable equalizer or
cable driver with integrated reclocker
• Supports ST-424 (3G), ST-292 (HD), and ST-259
(SD)
• Compatible with DVB-ASI and AES10 (MADI)
• Integrated reclocker locks to SMPTE rates of 2.97
Gbps, 1.485 Gbps, or divide-by-1.001 subrates
and 270 Mbps
• On-Chip 75-Ω termination and return loss
compensation network
• EQ (equalizer) mode:
– Adaptive cable equalizer with integrated
reclocker
– 100-Ω Output driver with de-emphasis
– Reclocked 75-Ω loop-through output
– EQ mode cable reach
(Belden 1694A, SDI_OUT Disabled):
– 200 m at 2.97 Gbps
– 300 m at 1.485 Gbps
– 600 m at 270 Mbps
• CD (cable driver) mode:
– Dual differential output cable drivers with
integrated reclocker
– Adaptive PCB input equalizer
– Reclocked 100-Ω loopback output
• Automatic pre-emphasis and slew rate control on
75-Ω outputs
• Polarity inversion on 75-Ω and 100-Ω outputs
• Automatic power save in absence of input signal
– Power dissipation: 25 mW (typical)
• Power-down control through ENABLE pin
• Single 2.5-V supply
– EQ mode power dissipation: 275 mW (typical)
– CD mode power dissipation: 290 mW (typical)
• Programmable through pins, SPI, or SMBus
interface
• –40°C to +85°C Operating temperature range
• 5-mm × 5-mm, 32-Pin WQFN package
• Pin compatible with the LMH1297 for easy
upgrade to 12G-SDI

2 Applications
• SMPTE compatible serial digital interface
• UHDTV/4K/8K/HDTV/SDTV video
• IP media gateway
• Digital video processing and editing

3 Description
The LMH0397 is a 3G-SDI 75-Ω bidirectional I/O with
integrated reclocker. This device can be configured
either in input mode as an adaptive cable equalizer or
in output mode as a dual cable driver, allowing
system designers the flexibility to use a single BNC
either as an input or output port to simplify HD-SDI
video hardware designs. The integrated reclocker
locks to all supported SMPTE data rates up to 2.97
Gbps in both modes. The bidirectional I/O has an onchip
75-Ω termination and return loss compensation
network that meets the stringent SMPTE return loss
requirements.
An additional 75-Ω driver output allows the LMH0397
to support a variety of system functions. In EQ
(Equalizer) Mode, this second 75-Ω driver can be
used as a loop-through output. In Cable Driver (CD)
Mode, this 75-Ω driver can be used as a second fanout
cable driver. The host-side 100-Ω driver can also
be used as a loopback output in CD Mode for
monitoring purposes.