October 1994

13

Philips Semiconductors

Product specification

Satellite sound circuit with noise reduction

TDA8740; TDA8740H

Notes

1. At pin 20 (16) the demodulated 1 kHz signal should be present with a typical level of 158 mV (RMS) (

−16 dBV), and

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

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.

Output selector control circuit (see also Table 2) and main channel PLL lock-in select [MCS pin 7 (2)]; pins 15,

17, 26 and 13 (10, 13, 22 and 8) are MOS inputs and should not be left open-circuit

LOW level input voltage limits

0

−

1.2

V

MID level input voltage limits

for MCS pin only

1.8

−

2.8

V

MID level input voltage on

MCS pin if MCS pin is floating

19

21

HIGH level input voltage limits

3.5

−

V

low input resistance MCS pin

to ground

12

19

26

k

Ω

high input resistance MCS pin

52

80

108

k

Ω

LOW level input current

(not MCS pin)

−<−1

−µA

HIGH level input current

(not MCS pin)

−<1

−µA

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT