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LVDS_PPEN: +3.3V_S electrical level Output, Panel Power Enable signal. It can be used to turn On/Off the connected LVDS display.
LVDS_BLEN: +3.3V_S electrical level Output, Panel Backlight Enable signal. It can be used to turn On/Off the backlight's lamps of connected LVDS display.
LVDS_BLT_CTRL/GP_PWM_OUT0: this signal can be used to adjust the panel backlight brightness in displays supporting Pulse Width Modulated (PWM)
regulations. When backlight brightness control via PWM is not required, this signal can be used as a General Purpose PWM output (+3.3V_S electrical level).
LVDS_BLC_DAT: I2C control data line for external Spread Spectrum Control Clock chip. Bidirectional signal, electrical level +3.3V_S with a 4k7Ω pull-up resistor.
LVDS_BLC_CLK: I2C control clock line for external Spread Spectrum Control Clock chip. Bidirectional signal, electrical level +3.3V_S.
3.2.3.9 HDMI interface signals
Besides LVDS interface, NXP i.MX6 processor also has an embedded HDMI Tx module, which provides a HDMI standard interface for HDMI1.4a compliant
displays. By using HDMI interface along with two LVDS single channel interfaces, it is possible to drive up to 3 independent displays.
Signals involved in HDMI management are the following:
TMDS_CLK+/TMDS_CLK-: TMDS differential Clock.
TMDS_TX0+/TMDS_TX0-: TMDS differential pair #0
TMDS_TX1+/TMDS_TX1-: TMDS differential pair #1
TMDS_TX2+/TMDS_TX2-: TMDS differential pair #2
HDMI_CTRL_DAT: DDC Data line for HDMI panel. Bidirectional signal, electrical level +3.3V_S with a 4k7Ω pull-up resistor.
HDMI_CTRL_CLK: DDC Clock line for HDMI panel. Bidirectional signal, electrical level +3.3V_S with a 4k7Ω pull-up resistor.
HDMI_CEC: HDMI Consumer Electronics Control (CEC) Line. Bidirectional signal, electrical level +3.3V_S.
HDMI_HPD#: Hot Plug Detect Input signal. +3.3V_S electrical level signal with 100kΩ pull-down resistor
Since HDMI Tx module is embedded in the i.MX6 processors it is not necessary to implement voltage level shifter for TMDS differential pairs on the Carrier board. It
is still necessary, however, to implement voltage level shifters on Control data/Clock signals, as well as for Hot Plug Detect signal.
Please refer to the following schematics as an example of implementation of voltage level shifters on the carrier board.
Q7-928
Q7-928 User Manual - Rev. First Edition: 1.0 - Last Edition: 3.0 - Author: S.B. - Reviewed by P.Z Copyright © 2016 SECO S.r.l.
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