SAA7282 Datasheet, PDF (8/25 Pages) NXP Semiconductors – Terrestrial Digital Sound Decoder TDSD2

Philips Semiconductors
Terrestrial Digital Sound Decoder (TDSD2)
Product specification
SAA7282
AMOGMDIS
This bit enables and disables the automute function (which
is activated according to the error limit registers).
Power-on resets to enabled (i.e. AMDIS = logic 0). AMDIS
should be disabled for the user definable mute (MUTE) to
be used.
MUTEDEF
This defines the operation of the user definable MUTE pin
when it is pulled LOW externally. If MUTEDEF is HIGH and
RSSF = logic 1, the output of the device is switched to FM
input. If MUTEDEF is HIGH and RSSF = logic 0, or if
MUTEDEF is LOW, the output is muted. Power on resets
to LOW.
ERROR LIMIT REGISTERS
UPPER ERROR LIMIT REGISTER
This defines the number of errors in 128 ms period which
will cause automute to switch IN. User definable, but
power on resets to 50 Hex.
LOWER ERROR LIMIT REGISTER
This defines the number of errors in 128 ms period which
will cause automute to switch OUT. User definable, but
power on resets to 14 Hex.
Table 2 Output as a function of M1/M2 and DMSEL.
DMSEL
0
0
1
1
M1/M2
0
1
0
1
FUNCTION
selects DIGITAL; L = M2, R = M2
selects DIGITAL; L = M1, R = M1
selects DIGITAL; L = M2, R = M1
selects DIGITAL; L = M1, R = M2
Table 3 Port 2 control.
PORT2
0
1
PIN OUTPUT STATE
LOW
HIGH
Table 4 SSWIT signal states and function.⁽¹⁾
SSWIT3
0
0
0
0
1
1
SSWIT2
0
0
1
1
x
x
SSWIT1
0
1
0
1
0
1
FUNCTION
NICAM source de-emphasis switched out, no gain
NICAM source de-emphasis switched in, no gain
NICAM source de-emphasis switched in, −6 dB gain; power-on reset state
NICAM source de-emphasis switched in, +12 dB gain
external inputs switched in, no change to previous de-emphasis/gain setting
FM inputs switched in, no change to previous de-emphasis/gain setting
Note
1. Where x = don’t care.
July 1993
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