Overview

The LC7455A/M extracts the closed caption signal superimposed on a video signal during the vertical return period and, under the control of a clock signal provided by the decoder IC, transfers that signal to the IC (usually a microcontroller) that decodes the closed caption data. The LC7455A/M supports four operating modes. Modes 1 and 2 can be used for XDS. In these modes, the LC7455A/M, in combination with the decoder IC (microcontroller), extracts the caption signal superimposed on field 2 and uses it for NTSC VCR functions such as the automatic time and date setting function. In modes 3 and 4, the LC7455A/M, in combination with the decoder IC (microcontroller), extracts the caption signal superimposed on fields 1 and 2 and uses it for NTSC TV applications (mode 3) or PAL TV applications (mode 4).

Functions

• Low power dissipation achieved by fabrication in a CMOS process.

• Stable caption signal extraction achieved by a built-in peak hold circuit and the use of digital technology.

• Operating supply voltage: 5 V ±10

• Package LC7455A: 16-pin DIP LC7455M: 18-pin MFP