Sony CXA1691AS, CXA1691AM Datasheet

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E98425-TE

Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.

Absolute Maximum Ratings (Ta=25 °C)

• Supply voltage VCC 14 V

• Operating temperature Topr –10 to +60 °C

• Storage temperature Tstg –50 to +125 °C

• Allowable power dissipation

PD 700 mW

(CXA1691AM)

PD 1000 mW

(CXA1691AS)

Recommended Operating Conditions

Supply voltage VCC 2 to 7.5 V

(CXA1691AM)

VCC 2 to 8.5 V

(CXA1691AS)

Description

CXA1691AM/AS is a one-chip FM/AM radio IC

designed for radio-cassette tape recorders.

Features

• Small number of peripheral components.

• Low current consumption (VCC=3 V)

For FM : ID=5.8 mA (Typ.) For AM : ID=4.7 mA (Typ.)

• Built-in FM/AM select switch.

• Large output of AF amplifier.

VCC=6 V, EIAJ output=450 mW (Typ.) when load impedance 8 Ω

Function

FM section

• RF amplifier, Mixer and OSC (incorporating AFC variable capacitor).

• IF amplifier

• Quadrature detection

• Tuning LED driver

AM section

• RF amplifier, Mixer and OSC (with RF AGC)

• IF amplifier (with IF AGC)

• Detector

• Tuning LED driver

AF section

• Electronic volume control

• FM muting

Structure

Bipolar monolithic IC

FM/AM Radio

CXA1691AM CXA1691AS

28 pin SOP (Plastic) 30 pin SDIP (Plastic)

CXA1691AM/AS

For the availability of this product, please contact the sales office.

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CXA1691AM/AS

Block Diagram

CXA1691AM

CXA1691AS

28 27 26 25 24 23 22 21

20 19 18 17 16

15

FM/AM

BAND

SELECT

AM

IF IN

FM

IF INNCMETER

IF

GND

AFC AGC

DET OUT

AF

IN

Ripple

FILTERV

CC

AF

OUTGND

MUTE FM

DISCRI

NF AM

OSC

AFC FM

OSC

Reg

OUTFMRFAMRF IN

NC FM

RF INFEGND

FM/AM

FE OUT

VOL

1 2 3 4 5 6 7 8 9

10 11 12 13 14

AM IF DET AGC

TUNING METER

FM IF

AM FE

FM

DISCRIMINATOR

FM FE

AF POWER AMP

28 27 26 25 24 23 22 21

20 19 18 17 16

15

FM/AM

BAND

SELECT

AM

IF IN

FM

IF INNCMETER

IF

GND

AFC AGC

DET OUT

AF

IN

Ripple

FILTERV

CC

AF

OUTGNDGND

MUTE FM

DISCRI

NF AM

OSC

AFC FM

OSC

Reg

OUTFMRFAMRF IN

NC FM

RF INFEGND

FM/AM

FE OUT

VOL

1 2 3 4 5 6 7 8 9

10 11 12 13 14

2930

NC

AF POWER AMP

TUNING METER

FM

DISCRIMINATOR

AM IF DET AGC

AM FE

FM FE

FM IF

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CXA1691AM/AS

Standard Circuit Design Data (The pin numbers in the parenthesis are for CXA1691AS.)

Voltage (V)

No. Symbol VCC=3 V VCC=6 V Equivalent circuit Description

FM AM FM AM

1

(1, 2)

2 (3)

3 (4)

27 (28)

4 (5)

5 (6)

6 (7)

8 (9)

7 (8)

MUTE

FM DISCRI

NF

AF OUT

VOL CONT

AM OSC

AFC

REG OUT

FM OSC

0 0 0 0

2.18 2.70 4.88 5.43

1.5 1.5 3.0 3.0

1.25 1.25 1.25 1.25

1.25 ∗ 1.25 ∗

1.25 1.25 1.25 1.25

2

1k

1.2k

3

27

V

CC

GND

×100

4

GND

20k

80k

5

3.6k

6

8

1.25V (REG)

7

Phase-shift circuit Connect ceramic discriminator

Negative feedback pin

Power amplifier output pin

Connect variable resistor for electronic volume control.

AM local oscillation circuit

AFC variable capacitor pin

Regulator pin 1.25 V (Typ.)

FM local oscillation circuit

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CXA1691AM/AS

Voltage (V)

No. Symbol VCC=3 V VCC=6 V Equivalent circuit Description

FM AM FM AM

9 (10)

12 (13)

10 (11)

11 (12)

13 (14)

14 (15)

15 (16)

16 (17)

17 (18)

18 (19)

FM RF

FM RF IN

AM RF IN

NC GND

(FE GND)

FM/AM FE OUT

BAND SELECT

AM IF IN

FM IF IN

NC

1.25 1.25 1.25 1.25

0.3 0 0.3 0

1.25 1.25 1.25 1.25

0 0 0 0

0.36 0.2 0.36 0.2

0.84 0 0.88 0

0 0 0 0

1.30 0 1.30 0

0 0 0 0

9

3p

8k

1k

12

10

V

CC

AM FM

220

14

15

GND

V

CC

16

2k

GND

17

360

Connect FM RF tuning coil

FM RF input pin

AM RF input pin

IF output pin of FM and AM. Connect IF filter.

FM and AM bands selection switch pin. During GND it becomes AM and during open it becomes FM.

Input pin of AM IF.

Input pin of FM IF.