STV82X8 datasheet(18/157 Pages) STMICROELECTRONICS

Part #	STV82X8

Description	Digital Audio Decoder / Processor for BTSC Television/Video Recorders

PDF	157 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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18 / 157 page

System Clock

STV82x8

18/157

System Clock

The System Clock integrates 2 independent frequency synthesizers.

The first frequency synthesizer is used by the demodulator at a frequency of 24.576 MHz.

The second frequency synthesizer is used by the DSP core and can be adjusted between 100 and

150 MHz depending on the application.

The default values are designed for a standard 27-MHz reference frequency provided by a stable

single crystal oscillator or an external differential clock signal (for example, from the STV35x0)

depending on the CLK_SEL pin configuration (CLK_SEL = 1 means a single crystal oscillator, 0

means an external differential clock).

The 27-MHz value is the recommended frequency for minimizing potential RF interference in the

application. The sinusoidal clock frequency, and any harmonic products, remain outside the TV

picture and sound IFs (PIF/SIF) and Band-I RF.

Note:

A change in the reference frequency is compatible with other default I²C programming values,

including those of the built-in Automatic Standard Recognition System.

STV82X8 Datasheet(PDF) 18 Page - STMicroelectronics