GS2989

Final Data Sheet

Rev.6

GENDOC-052133

July 2015

11 of 20

Semtech

www.semtech.com

4.3.1 Slew Rate Selection (Rise/Fall Time Requirement)

The GS2989 supports two user-selectable output slew rates.

Control of the slew rate is determined by the setting of the SD/HD input pin.

4.4 Output Disable

The GS2989 supports an output disable function for each serial data differential output.

Control of this function is determined by the setting of the DISABLE1 and DISABLE2

control pins.

The serial output disables (DISABLE1 and DISABLE2), disable power to the current mode

serial data output drivers. When asserted LOW, the SDO/SDO output drivers are

powered-down.

When DISABLE1 and DISABLE2 are driven LOW simultaneously, the entire device is

powered down, and the power consumption is minimized.

4.5 Output Signal Presence Indicator (OSP)

The GS2989 supports an output signal presence indicator function.

The output signal presence pin (OSP) is an active-low output that indicates when a valid

output signal has been detected at the pre-driver output.

Table 4-2: Slew Rate Selection

SD/HD

Rise/Fall Time

0

SMPTE 424M & 292M compliant

1

SMPTE 259M compliant

Floating

SMPTE 259M compliant

Table 4-3: Output Disable

DISABLE1

DISABLE2

SDO1/SDO1

SDO2/SDO2

0

0 or Floating

All Chip Power Down

0

1

High-Impedance

Operational

1 or Floating

0 or Floating

Operational

High-Impedance

1 or Floating

1

Operational

Operational

Floating

Floating

Operational

High-Impedance