Datasheet
FIGURE 1. SD387 Evaluation Board
Inputs and Outputs: BNC_IO Input/Output, SDI Input, and SDO Output
The bidirectional I/O (J1) is a 75Ω BNC connector. When the LMH0387 is configured as an input, the input signal
on the BNC_IO pin should conform to the SMPTE 424M, SMPTE 292M, or SMPTE 259M standards. When the
LMH0387 is configured as an output, the BNC_IO pin will drive SMPTE SDI signal levels (800 mV
P-P
into 75Ω).
The SDI input connectors (J2 and J3) are 50Ω SMA connectors. This cable driver input includes a 100Ω differential
termination resistor (R5) at the LMH0387 device and is optimized for 100Ω differential input.
The SDO output connectors (J4 and J5) are 50Ω SMA connectors. When using only one side of this equalizer
output pair, the other side should be terminated with a 50Ω SMA termination. For example, when only using the
SDO output, SDO
¯¯¯¯
should be terminated with a 50Ω SMA termination.
SD387EVK User Guide 2 of 23
Rev 1.1 © 2010 National Semiconductor Corp.