MSP3410D View Datasheet(PDF) - Micronas

Part Name

Description

Manufacturer

MSP3410D

Multistandard Sound Processors

Micronas 

PRELIMINARY DATA SHEET

MSP 34x0D

4.1.2. Quadrature Mixers

The digital input coming from the integrated A/D con-

verter may contain audio information at a frequency

range of theoretically 0 to 9 MHz corresponding to the

selected standards. By means of two programmable

quadrature mixers, two different audio sources, for

example NICAM and FM-Mono, may be shifted into

baseband position. In the following, the two main

channels are provided to process either:

– NICAM (MSP-Ch1) and FM/AM mono (MSP-Ch2)

simultaneously or, alternatively:

– FM-Mono (Ch2)

– FM2 (MSP-Ch1) and FM1 (MSP-Ch2).

Two programmable registers, to be divided up into a

low and a high part, determine frequency of the oscilla-

tor, which corresponds to the frequency of the desired

audio carrier.

4.1.3. Low-pass Filtering Block

for Mixed Sound IF Signals

Data shaping and/or FM bandwidth limitation is per-

formed by a linear phase finite impulse response (FIR)

filter. Just like the oscillators’ frequency, the filter coeffi-

cients are programmable and are written into the IC by

the CCU via the control bus. Thus, for example, differ-

ent NICAM versions can easily be implemented. Two

not necessarily different sets of coefficients are

required, one for MSP-Ch1 (NICAM or FM2) and one

for MSP-Ch2 (FM1 = FM-mono). In a corresponding

table several coefficient sets are proposed.

VREFTOP

AD_CV[7:1]

ANA_IN1+

ANA_IN2+

AGC

AD

AD_CV[8]

ANA_IN-

FRAME

NICAMA

DCO2

Pins

Internal signal lines (see fig. 4–2)

Demodulator Write Registers

DCO1

Oscillator

Mixer

FIR1

Lowpass

MODE_REG[6]

Phase and

AM Dis-

crimination

DQPSK

Decoder

Phase

Differen-

tiator

MSP sound IF channel 1

(MSP-Ch1: FM2, NICAM)

Amplitude

Carrier

Detect

AD_CV[9]

MSP3410D only

NICAM

Decoder

Mute

Lowpass

Mixer

MSP sound IF channel 2

(MSP-Ch2: FM1, AM) Amplitude

Carrier

Detect

Mixer

Oscillator

Lowpass

FIR2

Phase and

AM Dis-

crimination

Phase

Differen-

tiator

Mute

MODE_REG[8]

Lowpass

DCO2

Fig. 4–2: Architecture of demodulator and NICAM decoder section

ADR

NICAMA

NICAMB

FM2

IDENT

FM1/AM

Micronas

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