Sharp LC-32LE340E - Circuit Descriptions

LC-32LE340/343
LC-40LE340/343
2. TUNER
CIRCUIT DESCRIPTIONS
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Sound system output is supplying 2x8W (10%THD) for stereo 8speakers
Supported peripherals are:
x 1 RF input VHF I, VHF III, UHF @ 75Ohm(Common)
x 1 Side AV (CVBS, R/L_Audio)
x 2 SCART socket(Common)
x 1 YPbPr (Common)
x 1 Side S-Video(Common)
x 1 PC input(Common)
x 4 HDMI 1.3 input(Common)
x 1 Common interface(Common)
x 1 Optic S/PDIF output(Common)
x 1 Stereo audio input for PC(Common)
x 1 Subwoofer output(Common)
x 1 Headphone(Common)
x 2 USB(Common)
x 1 Bluray/DVD(Optional)
x 1 Ethernet-RJ45 (Common)
x 1 External Touchpad(Common)
2. TUNER
FT 2112/3/8/9 are newly developed Half-NIM modules designed for both digital
(DVB-T / T2 and DTMB for terrestrial China) and analog TV reception in compliance with
the European ATV standards for analogue, as well as with the terrestrial standard ETS 300
744 for DVB-T and the new terrestrial standard ETS 302 755 for DVB-T2. It consists of a 3-
band RF tuner, which receives RF signal and down-converts it to an IF frequency of 36MHz
for digital and 38.9MHz for analog IF. The analogue IF output can directly drive a SAW
filter. A digital IF Stage, which consists of one SAW filter & gain-controllable IF that offers a
sufficient output level to be connected directly to an A/D converter.
In active antenna option, the following circuit are used. ANT_CTRL pin is controlled by
microcontroller. If ANT_CTRL is low, ANT_PWR will be low. If ANT_CTRL is high,
ANT_PWR will be high. OVER_CUR_DETECT pin is a monitor for short circuit in antenna.
OVER_CUR_DETECT is low, ANT_CTRL will be low, so ANT_PWR will be low. Finally,
short circuit protection is done by circuits and microcontroller.
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Active Antenna Circuit
1.1. Features of FT2112
• Digital DVB-T T2, DTMB & analogue (48.25MHz to 863.25MHz) reception
• Single 5V supply voltage only
• Built-in 5-33V DC-DC converter
• Single power supply to the RF tuner & IF VGA amplifier section
• Bus Control switch-able RF AGC function:
a) Wide Band AGC for optimum strong signal performance
b) Conventional AGC for optimum analog reception
• RF AGC information via I2C Bus
• Tuner power standby mode via I2C Bus
• Small size (56 mm x 29 mm x 10 mm)
• I2C (SDA & SCL) bus control interface
• ROHS compliant
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LC-32LE340/343
LC-40LE340/343