5

FN6716.0

June 4, 2008

Pin Descriptions

SYMBOL

DESCRIPTION

RX0-, RX0+, RX1-, RX1+, RX2-, RX2+ TMDS Inputs. Incoming TMDS data signals.

RXC-, RXC+

TMDS Inputs. Incoming TMDS clock signals.

TX0-, TX0+, TX1-, TX1+, TX1-, TX1+

TMDS Outputs. TMDS output data for selected channel.

TXC-, TXC+

TMDS Outputs. TMDS output clock for selected channel.

SCL

Digital input, 5V tolerant, 500mV hysteresis. Serial data clock for 2-wire interface.

Note: Internal 65k

Ω pull-up to V

SDA

Bidirectional Digital I/O, open drain, 5V tolerant. Serial data I/O for 2-wire interface.

Note: Internal 65k

Ω pull-up to V

ADDR[6:0]

Digital inputs, 5V tolerant. 7-Bit address for serial interface.

Note: Internal 60k

Ω pull-down to GND.

AD

Digital Output, 3.3V. AD = Activity Detect. Output goes high when an active TMDS clock is detected on

RXC.

RES_BIAS

Tie to GND through a 3.16k external resistor. Sets up internal bias currents.

RES_TERM

Tie to VD through a 1.0k 1% external resistor. During calibration, the termination resistor closest in value

to RES_TERM/20 (= 50

Ω) is selected.

PD

Digital Input, 3.3V. PD = Power-down. Pull high to put the ISL54105A in a minimum power consumption

mode.

Note: To ensure proper operation, this pin must be held low during power-up. It may be taken high 100ms

after the power supplies have settled to 3.3V ±10%.

When exiting Power-down, a termination resistor Recalibration cycle must be run to re-trim the

termination resistors (see register 0x03[7]).

Note: Internal 60k

Ω pull-down to GND.

RESET

Digital Input, 3.3V. Pull high then low to reset the mux. Tie to GND in final application.

Note: Internal 60k

Ω pull-down to GND.

TEST

Digital Input. Used for production testing only. Tie to GND in final application. This pin has an internal

pulldown to GND, so it is also acceptable to leave this pin floating.

Power supply. Connect to a 3.3V supply and bypass each pin to GND with 0.1µF.

THERMAL PAD (GND)

Ground return for the entire chip. The thermal pad must have a low impedance connection to GND for

the ISL54105A to function at all. The lower electrical impedance, the better the ground, and the better the

performance. A low thermal impedance between the thermal pad and the GND plane of the PCB will

dissipate the heat from the package more efficiently as well and is recommended.

ISL54105A