saa7706h NXP Semiconductors, saa7706h Datasheet - Page 19

• Manufacturer Part Number: saa7706h
• Description: Car Radio Digital Signal Processor Dsp
• Manufacturer: NXP Semiconductors

Philips Semiconductors
The outputs of the stereo decoder to the DSP1, which are
all running on a sample frequency of 38 kHz are:
2001 Mar 05
handbook, full pagewidth
Pilot presence indication: pilot-I. This 1-bit signal is LOW
for a pilot frequency deviation <4 kHz and HIGH for a
pilot frequency deviation >4 kHz and locked on a pilot
tone.
‘Left’ and ‘right’ FM reception stereo signal: this is the
18-bit output of the stereo decoder after the matrix
decoding.
Noise level (see also Section 8.4.1): which is retrieved
from the high-pass output of the MPX filter. The noise
level is detected and filtered in the DSP1 and is used to
optimize the FM weak signal processing.
Car radio Digital Signal Processor (DSP)
(dB)
100
20
40
60
80
0
0
10
Fig.11 Transfer of MPX signal at the output of the stereo decoder.
20
30
19
Normally the FM_MPX input and the FM_RDS input have
the same source. If the FM input contains a stereo radio
channel, the pilot information is switched to the Digitally
Controlled Sampling (DCS) clock generation and the DCS
clock is locked to the 256
this locked frequency is also used for the RDS path
ensuring the best possible performance.
Except from the above mentioned theoretical response
also the non-flat frequency response of the ADC has to be
compensated in the DSP1 program.
40
50
60
38 kHz of the pilot. In this case
f (kHz)
Product specification
SAA7706H
70
MGT467