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 on-chip 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 fan-out cable driver. The host-side 100-Ω driver can also be used as a loopback output in CD Mode for monitoring purposes.
The on-chip reclocker attenuates high-frequency jitter and fully regenerates the data using a clean, low-jitter clock. The reclocker has a built-in loop filter and does not require any input reference clock. The LMH0397 also has an internal eye opening monitor and a programmable pin for CDR lock indication, input carrier detect, or hardware interrupts to support system diagnostics and board bring-up.
The LMH0397 is powered from a single 2.5-V supply. The device is offered in a small 5-mm × 5-mm, 32-pin WQFN package. The LMH0397 is also pin-compatible with the LMH1297.