TDA8741 Datasheet, PDF (13/24 Pages) NXP Semiconductors – Satellite sound circuit with noise reduction

Philips Semiconductors
Satellite sound circuit with noise reduction
Product specification
TDA8741; TDA8741H
Notes to the AC characteristics
1. At pin 20 (16) the demodulated 1 kHz signal should be present with a typical level of 158 mV (RMS) (−16 dBV), and
THD of maximum 0.5%; V_P = 8 to 13.2 V; T_amb = −20 to +70 °C.
2. Modulation of main channel is OFF; modulation of secondary channels is ON.
3. The electrolytic capacitors at pins 40 and 42 (36 and 38) are removed and 1500 pF capacitors between pin 40 (36)
and ground and between pin 42 (38) and ground are connected. At pins 40 and 42 (36 and 38) the demodulated
1 kHz signals should be present with typical levels of 9 mV (RMS) and THD of maximum 0.5%; V_P = 8 to 3.2 V;
T_amb = −20 to +70 °C.
4. All PLLs locked; R_S1 = R_S2 = 0.68 kΩ.
5. Modulation of secondary channel being measured and main channel is OFF; modulation of other secondary channel
is ON.
6. Modulation of main channel is ON; modulation of secondary channels is OFF.
7. Measured at pins 38 (34) (left) and 30 (26) (right) and no electrolytic capacitors connected to these pins.
Table 1 Truth table for output selection (note 1)
SWITCH
POSITION
1
2
3
4
5
6
7
STATE
stereo
left
right
main
external
mute secondary
mute all
PIN 15 (10)
OUTSEL L
1
1
0
0
X
X
X
Note
1. X = don’t care.
PIN 17 (13)
OUTSEL R
1
0
1
0
X
X
X
PIN 26 (22)
EXT/INT
0
0
0
0
1
0
1
PIN 13 (8)
MUTE
0
0
0
0
0
1
1
October 1994
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