LM3189 FM IF System. General Description. Provides a specific circuit for flexible audio output

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                                                                          April 1987

LM3189 FM IF System

General Description                                               Features

The LM3189N is a monolithic integrated circuit that provides Y Exceptional limiting sensitivity: 12 mV typ at b3 dB all the functions of a comprehensive FM IF system. The point

block diagram of the LM3189N includes a three stage FM IF Y Low distortion: 0.1% typ (with double-tuned coil) amplifier/limiter configuration with level detectors for each Y Single-coil tuning capability stage, a doubly balanced quadrature FM detector and an Y Improved (S a N)/N ratio audio amplifier that features the optional use of a muting Y Externally programmable recovered audio level

(squelch) circuit.

Y Provides specific signal for control of inter-channel mutThe advanced circuit design of the IF system includes desir- ing (squelch) able deluxe features such as programmable delayed AGC Y Provides specific signal for direct drive of a tuning mefor the RF tuner, an AFC drive circuit, and an output signal ter to drive a tuning meter and/or provide stereo switching logY On channel step for search control

ic. In addition, internal power supply regulators maintain a

Y Provides programmable AGC voltage for RF amplifier nearly constant current drain over the voltage supply range

of a8.5V to a16V.                                                                                        Y Provides a specific circuit for flexible audio output

Y Internal supply voltage regulators

The LM3189N is ideal for high fidelity operation. Distortion

in an LM3189N FM IF system is primarily a function of the Y Externally programmable ON channel step width, and phase linearity characteristic of the outboard detector coil. deviation at which muting occurs

The LM3189N has all the features of the LM3089N plus additions.

The LM3189N utilizes the 16-lead dual-in-line plastic package and can operate over the ambient temperature range of b40§C to a85§C.

Block Diagram

TL/H/7960–1

All resistance values are in X

*L tunes with 100 pF (C) at 10.7 MHz, Q0 j 75 (Toko No. KACS K586HM or equivalent)


        C1995 National Semiconductor Corporation             TL/H/7960                                                                                                                                                                                  RRD-B30M115/Printed in U. S. A.

Absolute Maximum Ratings

If Military/Aerospace specified devices are required, Power Dissipation (Note 2) 1500 mW please contact the National Semiconductor Sales Operating Temperature Range b40§C to a85§C

Office/Distributors for availability and specifications.

Storage Temperature Range                          b65§C to a150§C

Supply Voltage Between Pin 11 and Pins 4, 14                     16V

Lead Temperature (Soldering, 10 sec.)                              260§C

DC Current Out of Pin 12                                                     5 mA

DC Current Out of Pin 13                                                     5 mA

DC Current Out of Pin 15                                                     2 mA

Electrical Characteristics TA e 25§C, Vae 12V

Symbol

Parameter

Conditions

(See Single-Tuned Test Circuit)

Min

Typ

Max

Units

STATIC (DC) CHARACTERISTICS

I11

Quiescent Circuit Current

20

31

44

mA

DC Voltages:

V1

Terminal 1 (IF Input)

1.2

2.0

2.4

V

V2

Terminal 2 (AC Return to Input)

No Signal Input, Non Muted

1.2

2.0

2.4

V

V3

Terminal 3 (DC Bias to Input)

1.2

2.0

2.4

V

V15

Terminal 15 (RF AGC)

7.5

9.5

11

V

V10

Terminal 10 (DC Reference)

5

5.75

6

V

DYNAMIC CHARACTERISTICS

VI(lim)

Input Limiting Voltage (b3 dB Point)

fo e 10.7 MHz,

12

25

mV

AMR

AM Rejection (Term. 6)

VIN e 0.1V

AM Mod. e 30%

45

55

dB

VO(AF)

Recovered AF Voltage (Term. 6)

325

500

650

mV

THD

Total Harmonic Distortion (Note 1)

fmod e 400 Hz,

Single Tuned (Term. 6)

Deviation g75 kHz

0.5

1

%

Double Tuned (Term. 6)

VIN e 0.1V

0.1

%

S a N/N

Signal Plus Noise to Noise Ratio

(Term. 6)

65

80

dB

fDEV

Deviation Mute Frequency

fmod e 0

g40

kHz

V16

RF AGC Threshold

1.25

V

V12

On Channel Step

VIN e 0.1V

fDEV kg40 kHz fDEV lg40 kHz

0 5.6

V

Note 1: THD characteristics are essentially a function of the phase characteristics of the network connected between terminals 8, 9, and 10.

Note 2: For operation in ambient temperatures above 25§C, the device must be derated based on a 150§C maximum junction temperature and a thermal resistance of 80§C/W junction to ambient.

Connection Diagram

Dual-In-Line Package

TL/H/7960–2

Top View

Order Number LM3189N

See NS Package Number N16E

Test Circuits

Test Circuit for LM3189N Using a Single-Tuned Detector Coil

All resistance values are in X

*L tunes with 100 pF (C) at 10.7 MHz, Qo(unloaded) j 75 (Toko No. KACS K586HM or equivalent)

**C e0.01 mF for 50 ms de-emphasis (Europe) e 0.015 mF for 75 ms de-emphasis (USA)

TL/H/7960–3

Test Circuit for LM3189N Using a Double-Tuned Detector Coil

All resistance values are in X

*T:PRIÐQo(unloadedÐ j 75 (tunes with 100 pF

(C12)) 20t of 34e on 7/32× dia form

SECÐQo(unloaded) j 75 (tunes with 100 pF (C2)) 20t of 34e on 7/32× dia form kQ(percent of critical coupling) j 70% (adjusted for coil voltage (V ) e 150 mV

Above values permit proper operation of mute

(squelch) circuit ‘‘E’’ type slugs, spacing 4 mm

**C e0.01 mF for 50 ms de-emphasis (Europe) e 0.015 mF for 75 ms de-emphasis (USA)

TL/H/7960–4

Complete FM IF System for High Quality Tuners

The circuit provides a complete FM IF system for a high receiver requirements. See graph for Typical Limiting and quality receiver. Either one or two stages of amplification Noise Characteristics

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