MC44BC374CDTB 데이터 시트보기 (PDF) - Freescale Semiconductor

부품명

상세내역

제조사

MC44BC374CDTB

PLL Tuned UHF and VHF Audio/Video High Integration Modulator

Freescale Semiconductor 

Modulator Description Freescale Semiconductor, Inc.

13.11 Sound Section

The multivibrator oscillator is fully integrated and does not require any external components. An internal

low-pass filter and matched structure give a very low harmonics level.

The sound modulator system consists of the following two types:

• An FM modulator incorporating the sound subcarrier oscillator

• An AM modulator (MC44BC373C only)

The audio input signal is AC-coupled into the amplifier, which then drives both types of modulator.

The audio pre-emphasis circuit is a high-pass filter with an external capacitor and an internal resistor

(100kOhms). The recommended capacitor value (470pF) is for BG standard; time constant is 50µS.

13.12 Test Pattern Generator

The IIC generates a simple test pattern, which can be switched under bus control to permit a TV receiver to

easily tune to the modulator output. The pattern consists of two white vertical bars on a black background

and a 976Hz audio test signal.

TE2

7/10

3/10

TE1

0

10

20 24 2830

40 44 50

60 64

TIME IN µS.

Table 1. Test Pattern Generator

MC44BC373C/374C Technical Data

For More Information On This Product,

Go to: www.freescale.com

Share Link: