May 1992

2

Philips Semiconductors

Product specification

FM radio circuit for MTS

TDA7021T

GENERAL DESCRIPTION

The TDA7021T integrated radio receiver circuit is for portable radios, stereo as well as mono, where a minimum of

periphery is important in terms of small dimensions and low cost. It is fully compatible for applications using the

low-voltage micro tuning system (MTS). The IC has a frequency locked loop (FLL) system with an intermediate frequency

of 76 kHz. The selectivity is obtained by active RC filters. The only function to be tuned is the resonant frequency of the

oscillator. Interstation noise as well as noise from receiving weak signals is reduced by a correlation mute system.

Special precautions have been taken to meet local oscillator radiation requirements. Because of the low intermediate

frequency, low pass filtering of the MUX signal is required to avoid noise when receiving stereo. 50 kHz roll-off

compensation, needed because of the low pass characteristic of the FLL, is performed by the integrated LF amplifier.

For mono application this amplifier can be used to directly drive an earphone. The field-strength detector enables

field-strength dependent channel separation control.

Features

• RF input stage

• Mixer

• Local oscillator

• IF amplifier/limiter

• Frequency detector

• Mute circuit

• MTS compatible

• Loop amplifier

• Internal reference circuit

• LF amplifier for

− mono earphone amplifier or

− MUX filter

• Field-strength dependent channel separation control

facility

QUICK REFERENCE DATA

PACKAGE OUTLINE

16-lead mini-pack; plastic (SO 16; SOT109A); SOT109-1; 1996 July 24.

PARAMETER

CONDITIONS

SYMBOL

MIN.

TYP.

MAX.

UNIT

Supply voltage (pin 4)

1,8

−

6,0

V

Supply current

−

6,3

−

mA

RF input frequency

1,5

−

110

MHz

Sensitivity (e.m.f.) for

source impedance = 75

Ω;

−3 dB limiting

mute disabled

EMF

−

4

−µV

Signal handling (e.m.f.)

source impedance = 75

Ω

EMF

−

200

−

mV

AF output voltage

−

90

−

mV