SNLS558C April 2017 – May 2020 LMH0397
PRODUCTION DATA.
The EQ/CD_SEL pin selects the I/O as either an input (EQ Mode) or an output (CD Mode). The logic level applied to the EQ/CD_SEL pin automatically powers down the unused I/O direction. For example, if the LMH0397 is in EQ Mode (EQ/CD_SEL = L), the SDI_IO cable driver is powered down as shown in Table 2.
EQ/CD_SEL | INPUT | MODE | NOTES |
---|---|---|---|
L | SDI_IO+ | EQ Mode | 75-Ω video input to SDI_IO+.
OUT0± automatically enabled. SDI_IO Cable Driver powered down. |
H | IN0± | CD Mode | 100-Ω input to IN0±.
SDI_IO+ enabled as a cable driver output. SDI_OUT programmable as a secondary cable driver output. SDI_IO Equalizer powered down. |
The EQ/CD_SEL pin should be strapped at power up for normal operation. After power up, the EQ/CD_SEL pin state can be dynamically changed from EQ Mode to CD Mode and vice versa. When changing the EQ/CD_SEL state after power up, the signal flow to the reclocker is momentarily disturbed, and the chip automatically initiates a CDR reset to relock to the new input signal.