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TC-L42E3 LED Backlight Control Explanation
The LED Drive circuit receives 24V from the SMPS.
When IC8000 is satisfied of the presence of all the monitored sub-voltages, it provides the
Backlight_On command to turn on the LED drive circuit. This command enters the P-Board via pin
13 of connector P2 and travels to the LCD panel to turn on the LED drive circuit. The backlight
control signal, PWM, is delivered to the LED drive circuit via pin 1 of connector P4 to control the
brightness of the LEDs. The PWM signal is dependent on user settings and picture content. An
artificial intelligence circuit is used to manipulate the PWM signal for picture quality and reduced
power consumption. The LED drive circuit is responsible for controlling the amount of current that
passes through the LEDs.
To avoid catastrophic failures, when the LED backlight control circuit is defective, the
BACKLIGHT_SOS command is output to IC8000 to trigger the shutdown of the TV. The power
LED blinks one time.
Summary of Contents for TC-L19C30
Page 5: ...5 New Panel for 2011 IPS LED LCD ...
Page 6: ...6 Highlights ...
Page 7: ...7 The New World of Smart VIERA ...
Page 8: ...8 Concept of the IPTV World ...
Page 9: ...9 Evolution of the IPTV World and Its Future Expansion ...
Page 10: ...10 2D 3D Conversion ...
Page 16: ...16 TC L37DT30 Connectors ...
Page 24: ...24 TC L37DT30 Standby Power 2 ...
Page 28: ...28 TC L37DT30 Power On Operation ...
Page 30: ...30 TC L37DT30 Voltage Distribution ...
Page 32: ...32 TC L42E3 LED Backlight Control ...
Page 34: ...34 TC L37E3 LED Backlight Power Circuit ...
Page 36: ...36 TC L42D30 LED Backlight Power Circuit Waveform to one of the LED backlight connections ...
Page 39: ...39 TC L37DT30 Video Input and Process ...
Page 44: ...44 SOS Detect Shutdown ...
Page 46: ...46 TC L37DT30 Shutdown Circuit Block Diagram ...
Page 64: ...64 Troubleshooting Picture Problem Troubleshooting Picture Problem ...
Page 65: ...65 Horizontal Area Picture Problem ...
Page 66: ...66 Vertical Area Picture Problem ...
Page 67: ...67 Vertical Line Bar Problem ...
Page 68: ...68 Horizontal Line Picture Problem ...
Page 69: ...69 Non uniform Color Picture Problem ...
Page 70: ...70 Many Vertical Lines Picture Problem ...
Page 71: ...71 OSD Problem ...
Page 72: ...72 Strange Color Problem ...