GS2993 Dual Output Adaptive Cable Equalizer

Data Sheet

53966 - 4

August 2012

15 of 23

Propietary & Confidential

The Carrier Detect output pin (CD) indicates the presence of a valid signal at the input of

the GS2993. When CD is LOW, the device has detected a valid input on SDI and SDI.

When CD is HIGH, the device has not detected a valid input.

The Carrier Detect output still functions when the GS2993 is in sleep mode, such that a

valid Serial Digital Input can be detected at all times. In the sleep state, the carrier detect

functionality requires that the GAIN_SEL input be set to 0.

Auto-Sleep can be enabled by connecting CD to SLEEP. When connected, the GS2993

will automatically go into standby mode when there is a loss of Serial Digital Input

signal.

NOTE 1:

CD will only detect loss of carrier for data rates greater than 19Mb/s.

NOTE 2:

If the maximum cable length is exceeded (set by the SQ_ADJ pin) and the device

is not in Bypass mode, the CD pin will not be driven LOW, even if a carrier is present.

NOTE 3:

If the CD is connected to SLEEP, SQ_ADJ should either be left open, or

connected to ground.

Table 4-2: Sleep Input Table

Sleep

Function

0

The GS2993 operates normally

1

The GS2993 enters sleep mode. CD

output remains valid

Table 4-3: CD Output Table

CD

Input Status

0

Valid Input on SDI, SDI pins

1

Input is not valid