EQCO30T5.2 Datasheet, PDF (6/22 Pages) Microchip Technology – EQCO30T5.2 3G/HD-SDI Video Cable Driver

EQCO30T5.2
1.1.4 SD/HDB
With SD/HDB set to high, the output rise and fall times
are set for SD operation. When left floating or pulled
low, the rise and fall times are set for 3G/HD operation.
1.1.5 SDOn, SDOp
The output driver is not based on a CML output
stage. Both outputs operate independently, so there
is very little interference between the outputs and
their termination condition. There is also no LR-
output network needed for achieving good return-
loss. A 25Ω resistor should be connected in series
with the output to drive a 75Ω coax cable. The output
amplitude is achieved behind this 25Ω resistor; refer
to the application circuits at the end of the data
sheet. The PCB doesn’t require layout changes
when migrating from competing cable drivers,
however, fewer components are needed. One does
not need to optimize the return-loss network, since it
is omitted.
1.1.6 LFOUT
LFout provides the 5 Mbps received uplink signal
(LVTTL voltage levels). It can easily drive a PCB
trace of 20 pF at this speed. For longer distance
communication from this pin to the next chip, using a
buffer is recommended. The output impedance is
about 300Ω.
1.1.7 EQdis
When EQdis is left floating or pulled low, the input
trace equalization is turned on and invokes a typical
3 dB gain at 1.5 GHz.
This value is optimized for compensating the high-
frequency losses of approximately 20 cm of 5-mil
stripline in FR4. When pulled high, this equalization
is turned off.
DS60001303C-page 6
 2012-2016 Microchip Technology Inc.