Sony CXA1884N Datasheet

Low-voltage FM IF Amplifier

Description

The CXA1884N is designed for FM communication
devices. They incorporate a paging system, mixer, IF
limiter, FM detector, operational amplifier, comparator,
and others.

Features

• Low operating voltage 1.0 to 4.0V

• Low power consumption 2mA at 1.5V

• Built-in power source voltage monitor

Applications

IF Amplifier for Paging System Receiver

Structure

Bipolar silicon monolithic IC

Block Diagram and Pin Configuration

Absolute Maximum Ratings (Ta = 25°C)

• Supply voltage Vcc 7 V

• Operating temperature Topr –20 to +75 °C

• Storage temperature Tstg –65 to +150 °C

Recommended Operating Conditions

Supply voltage Vcc 1.0 to 4.0 V

– 1 –

E97Z05A8Y

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.

CXA1884N

20 pin SSOP (Plastic)

RF IN

OSC1

GND

OSC2

LVA

MIX OUT

BSV

V

CC

VB OUT

IF IN

SENSE

IF P1

NRZ

IF P2

COMP IN

QD

A2 IN

DET OUT

A1 OUT

A1 IN

MIXER

OSC

QUAD

DET.

A2

ERR.

AMP

REG.

IF LIM.

A1

2

3

4

5

6

7

8

9

10

1

11

16

17

18

19

20

12

13

14

15

Note) DET. : DETECTOR

LIM. : LIMITER
REG. :REGURATOR
ERR. : ERROR CORRECTION

– 2 –

CXA1884N

Pin Description

Pin
No.

1 OSC1

Those pins are connected to the external
parts of an oscillating circuit.
The oscillator is an internally-biased Colpitts
type with the collector, base, and emitter
connections at Vcc, pins 1 and 2
respectively.

Mixer output pin. Connect a 455kHz ceramic
filter between this pin and the IF IN pin.

Vcc pin.
Input pin for the IF limiter amplifier.

Connection pin of the bypass capacitor for
the IF limiter amplifier. Connect a capacitor of
about 0.047µF between this pin and ground
(or Vcc).

Connection pin of the bypass capacitor for
the IF limiter amplifier. Connect a capacitor of
about 0.047µF between this pin and ground
(or Vcc).

Connected to a quadrature detector phase
shifter.

OSC2

MIX OUT

VCC
IF IN

IF P1

IF P2

QD

2

3

4
5

6

7

8

Symbol Equivalent circuit Description

VCC

GND

2

1

VCC

GND

3

VCC

GND

5
6

VCC

GND

7

VCC

GND

8

– 3 –

CXA1884N

Pin

No.

9

DET OUT

Recovered signal output.

Symbol Equivalent circuit Description

9

VCC

GND

10

A1 IN

Input pin of inverting OP amplifier A1.

VCC

GND

10

11

A1 OUT

Output pin of OP amplifier A1.

VCC

GND

11

12

A2 IN

Input pin of OP amplifier A2.

VCC

GND

12

13

COMP
IN

Input pin of the comparator.
This pin is internally connected to the output
of OP amplifier A2.

VCC

GND

13

– 4 –

CXA1884N

Pin
No.

15

SENSE

Voltage control pin for external bias supply.

Symbol Equivalent circuit Description

VCC

GND

15

16

VB OUT

Supplies bias voltage to external circuit
transistors and others.

VCC

GND

16

20

RF IN

Mixer input pin.

20

VCC

GND

17

BSV

Reduces IC power consumption.
Lowering pin voltage beiow 0.35V stops IC
operation.

GND

17

18

LVA

Output pin for Low Voltage Alarm (LVA).
The pin turns to high impedance when
power voltage drops below 1.05V.

18

GND

19

GND

Ground pin.

14 NRZ

NRZ (Non Return Zero) output pin.

GND

14

– 5 –

CXA1884N

Electrical Characteristics

(VCC = 1.5V, Ta = 25°C, fs = 21.7MHz, fMOD = 256Hz, fDIV = 2.3kHz, AMMOD = 30%)

Item
Power consumption (during operation)
Power consumption

(during battery saving)
Input for –3dB Limiting

AM rejection ratio
OP amplifier input bias current

OP amplifier open loop gain
OP amplifier output voltage amplitude
Comparator hysteresis width
NRZ∗output leak current

NRZ∗saturation voltage
VB output current

VB output voltage
Sense voltage
LVA threshold voltage
LVA hysteresis width
LVA output leak current
LVA saturation voltage
Recovered signal voltage
BSV high level
BSV low level

ICC
ICCS
VIN (LIM)
AMRR
IBIAS

AV
VO
VTW
ILNRZ

VSATNRZ
IOUT

VBOUT
VSEN
VPML
VPMTH
ILLVA
VSATLVA
VDET
VTHBSV
VTLBSV

Test circuit 1
Test circuit 1

VI = 0.3V
Test circuit 3
VIN = 60dBµ

Test circuit 3
Test circuit 2
Test ciTcuit 4
Test circuit 5
Test circuit 6
Test circuit 7
ISINK = 200µA

Test circuit 8
VB = 0.9V
Test circuit 9
Test circuit 2
Test circuit 10
VPMH – VPML
Test circuit 7
Test circuit 8
Test circuit 3

1.2
—
—
25
—

45

0.25
30
—

—

0.1

0.95
85

1.00
35
—
—
10

0.95
—

2.0
—

7
—
30

60
—
40
—

—
—

—

100

1.05
50
—
—
—
—
—

2.6
20
—
—

100

—
—
50

5.0

0.4
—

—

115

1.10
70

5.0

0.4
—
—

0.35

mA

µA

dBµ

dB
nA

dB

Vp-p

mV

µA

V

mA

V

mV

V

mV

µA

V

mVrms

V
V

Symbol Condition Min. Typ. Max. Unit

∗

NRZ: Non Return Zero