LMH1229数据手册TI中文资料规格书

描述 Description

The LMH12x9 (LMH1229, LMH1239) is a long reach adaptive cable equalizer with integrated reclocker, dual outputs, and 75Ω loop-through output. The device is designed to equalize data transmitted over 75Ω coaxial cable and operates across SMPTE data rates ranging from 125Mbps to 11.88Gbps.

The adaptive equalizer at the SDI input enables automatic loss compensation for up to 100m Belden 1694A cable reach in 4K/8K video applications where 12G-SDI (11.88Gbps) is used. The integrated reclocker attenuates high frequency jitter and fully regenerates the data using a clean, low-jitter clock. The loop filter of the reclocker is adjustable with optional external capacitor for SDI cascade applications.

For routing simplicity and debug, the LMH12x9 features a 1:3 output mux consisting of two 100Ω fanouts with VOD and de-emphasis control and one 75Ω loop-through SDI output. The 75Ω loop-through output is provided to extend the signal reach or enable system-level diagnostics.

The LMH12x9 features internal integrated return loss networks that meet stringent SMPTE specifications across all data rates. The LMH12x9 also has an internal eye opening monitor and a programmable pin for CDR lock indication, input carrier detect, cable fault detection, or hardware interrupts to support system diagnostics and board bring-up.

The LMH1229 is pin compatible with the LMH1297 (12G UHD-SDI bidirectional I/O with integrated reclocker) when used in cable equalizer applications. For system-level redundancy, the LMH1239 is offered with an additional integrated SDI input mux.

特性 Features

Adaptive cable equalizer with integrated reclocker

Supports ST-2082-1(12G), ST-2081-1(6G), ST-424(3G), ST-292(HD), and ST-259(SD)

Compatible with DVB-ASI and AES10 (MADI)

Integrated referenceless reclocker locks to SMPTE rates: 11.88Gbps, 5.94Gbps, 2.97Gbps, 1.485Gbps, or divide-by-1.001 sub-rates, 270Mbps

Typical cable reach (Belden 1694A):

100m at 11.88Gbps (4Kp60 UHD)

150m at 5.94Gbps (UHD)

220m at 2.97Gbps (FHD)

300m at 1.485Gbps (HD)

600m at 270Mbps (SD) (Under Evaluation)



On-chip 75Ω termination and return loss compensation network

Input cable equalizer and reclocker features:

Improved cable reach with stress patterns

Programmable CDR loop bandwidth settings

2:1 75Ω input mux (LMH1239 only)



Output driver features:

1:2 100Ω fanout output with de-emphasis

Reclocked 75Ω loop-through output with cable fault detection (up to 600m)



Built-in PRBS generator, checker, and pathological pattern detector

Internal eye opening monitor

Single 2.5V supply

Low power: 375 mW (typical)

Power Save mode: 63 mW

Configurable by control pins, SPI, or SMBus interface

5mm × 5mm 32-pin WQFN package

Operating temperature range: –40°C to +85°C