Tuner(Tu102); Circuit Descriptions - Sharp LC-19LE510E Service Manual

LC-19LE510
LC-22LE510
LC-24LE510

2. TUNER(TU102)

A horizontal mounted and Digital Half-NIM tuner is used in the product, which covers 3 Bands(From 48MHz
to 862MHz for COFDM, from 45.25MHz to 863.25MHz for CCIR CH). The tuning is available through the
digitally controlled I2C bus (PLL). Below you will find info about the tuner.
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 logic 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.

CIRCUIT DESCRIPTIONS

24