SLLSF57A August 2022 – April 2024 TMDS1204
PRODUCTION DATA
The TMDS1204 transmitter supports both external (DC-coupled) and internal bias (AC-coupled) to a receiver. Selection between DC and AC-coupled is done through use of the AC_EN pin in pin-strap mode and TX_AC_EN register in I2C mode. The AC_EN pin informs the TMDS1204 whether or not an external AC-coupling capacitor is present. When AC_EN is greater than VIH, then TMDS1204 transmitters are internally biased to approximately VCC. For DisplayPort, HDMI 2.1 FRL AC-coupled, or any other AC-coupled application, the AC_EN pin should be connected to greater than VIH and an external AC-coupling capacitor should be placed on each of the OUT_D[2:0] pins and the OUT_CLK pin. If the AC_EN pin is connected to less than VIL, then the AC_EN pin will inform TMDS1204 that AC_EN pin is DC-coupled (externally biased) to the far-end HDMI compliant receiver.