March 1991

5

Philips Semiconductors

Preliminary specification

PLL FM demodulator for DBS signals

TDA8730

FUNCTIONAL DESCRIPTION

The TDA8730 is a PLL FM

demodulator intended for use in

satellite tuners. It can

demodulate frequency

deviations ranging from

to 25 MHz(p-p) (FSS services)

and offers a high demodulation

linearity. The circuit is optimized

for operation at 479.5 MHz (the

European IF for satellite tuners)

and can handle the various

broadcasting standards that are

in use (including MAC).

Due to the PLL principle,

demodulation noise threshold

extension is possible. The high

sensitivity of the balanced IF

input reduces the additional

gain, required in the tuner.

An on chip AGC circuit delivers a

gain control signal for use by the

tuner IF amplifier, and a voltage

regulator makes the circuit

insensitive supply voltage

changes.

LIMITING VALUES

In accordance with the Absolute Maximum System (IEC 134)

THERMAL RESISTANCE

SYMBOL

PARAMETER

MIN.

MAX.

UNIT

supply voltage

−0.3

11

V

input voltage

−0.3

V

output source current

−

10

mA

AGC output voltage

−

11

V

max short circuit time of outputs

10

−

s

AGC threshold adjustment voltage

−0.3

V

storage temperature

−55

150

°C

junction temperature

−

150

°C

operating ambient temperature

−25

85

°C

SYMBOL

PARAMETER

TYP.

MAX.

UNIT

from-junction-to-ambient in free air

55

−

K/W