Datasheet CXA3125N Datasheet (Sony)

—1—

E97705A85-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 –0.3 to +5.5 V

• Storage temperature Tstg –55 to +150 °C

• Allowable power dissipation

PD 625 mW

(when mounted on a printed circuit board)

Operating Conditions

• Supply voltage VCC 4.75 to 5.30 V

• Operating temperature Topr –20 to +75 °C

Description

The CXA3125N is a TV tuner IC which integrates
local oscillator and mixer circuits for VHF band, local
oscillator and mixer circuits for UHF band, and an IF
amplifier onto a single chip. This IC adopts a 16-pin
SSOP package and is suitable for miniaturizing
voltage synthesizer tuner.

Features

• Low noise figure

• Superior cross modulation

• Low power consumption (5 V, 43 mA typ.)

• IF output can be selected from symmetrical or

asymmetrical

• SSOP 16-pin package

Applications

• TV tuners

• VCR tuners

• CATV tuners

Structure

Bipolar silicon monolithic IC

All Band TV Tuner IC (VHF-CATV-UHF)

16 pin SSOP (Plastic)

CXA3125N

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

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CXA3125N

Block Diagram and Pin Configuration

CXA3125N

OUTPUT
Buffer

UHFOSC

IF AMP

UHFMIXVHFMIX

VHFOSC

IFout1

IFout2

UOSC2

BSW

UOSC1

VOSC2

IFSW

VOSC1

V

CC

MIXout1

MIXout2

GND

VHFin1

VHFin2

UHFin1

UHFin2

V.REG

Bias

1 2 6 7 83 4 5

15 14 12 11 10 916 13

—3—

CXA3125N

Pin Description and Equivalent Circuit

Pin

Symbol

Typical pin

Equivalent circuit Description

No. voltage (V)

1

2

3

4

5

6

7

8

9

11

VCC

MIXout1

MIXout2

GND

VHFin1

VHFin2

UHFin1

UHFin2

VOSC1

VOSC2

5.0

During VHF

reception 4.4

During UHF

reception 4.3

4.4

4.3

0

2.4

0

2.4

0

0

2.4

0

2.4

3.1

3.2

4.0

5.0

Power supply.

Mixer outputs and IF amplifier
inputs. These pins are output
with open collector, and they
must be connected to power
supply via load.

GND.

VHF inputs.
Normally a capacitor is
connected at Pin 5 to GND and
Pin 6 is used for input.

UHF inputs. Symmetrical input
to Pins 7 and 8 or a capacitor
is connected at Pin 8 to GND
and Pin 7 is used for input.

External resonance circuit
connection for VHF oscillators.

2 3

6

3k3k

5

8

3k3k

7

11

330

3k

8p

15p

3k

9

50

1

VCC

—4—

CXA3125N

Pin

Symbol

Typical pin

Equivalent circuit Description

No. voltage (V)

10

12

14

13

15

16

IFSW

UOSC1

UOSC2

BSW

IFout2

IFout1

0.8

(when open)

3.2

3.0

3.2

3.0

—

During

symmetrical

output 3.0

During

asymmetrical

output 4.3

During

symmetrical

output 3.0

During

asymmetrical

output 2.5

Symmetrical/asymmetrical
selection of IF output.
Asymmetrical output is selected
for open state; symmetrical
output, for connecting to GND.
When used as an asymmetrical
output, connect to GND with a
capacitor.

External resonance circuit
connection for UHF oscillators.

Band switching.
UHF operation when 3 V or
more voltage is applied
externally, and VHF operation
when 0.5 V or less voltage is
applied.

IF outputs during symmetrical
output. The reverse phase
signal to Pin 16 is output
during symmetrical output.
When asymmetrical output is
selected, the signal is not
output.

IF outputs.

3k 3k

1

VCC

1214

VCC

1

13

22k

32k

40k

VCC

1

30k

10

400

20k

400

30k

VCC

1

15

15

VCC

1

16

15

—5—

CXA3125N

Electrical Characteristics See the Electrical Characteristics Measurement Circuits 1 and 2.

(Ta=25 °C, VCC=5 V)

Item

Circuit current

Conversion gain

∗1

Noise figure

∗1, ∗2

1 % cross
modulation

∗1
∗3

Maximum
output power

Switch ON drift

∗4

+B drift

∗5

Band switch
voltage

Symbol
ICCVU
ICCVB
ICCUU
ICCUB
CG1U
CG2U
CG3U
CG4U
CG1B
CG2B
CG3B
CG4B
NF1
NF2
NF3
NF4

CM1

CM2

CM3

CM4
Pomax

(sat)

∆fsw1
∆fsw2
∆fsw3
∆fsw4
∆fst1
∆fst2
∆fst3
∆fst4

VSWV
VSWU

Measurement conditions
VHF operation asymmetrical output no input signal
VHF operation symmetrical output no input signal
UHF operation asymmetrical output no input signal
UHF operation symmetrical output no input signal
VHF operation fRF=55 MHz asymmetrical output
VHF operation fRF=360 MHz asymmetrical output
UHF operation fRF=360 MHz asymmetrical output
UHF operation fRF=800 MHz asymmetrical output
VHF operation fRF=55 MHz symmetrical output

∗6

VHF operation fRF=360 MHz symmetrical output

∗6

UHF operation fRF=360 MHz symmetrical output

∗6

UHF operation fRF=800 MHz symmetrical output

∗6

VHF operation fRF=55 MHz asymmetrical output
VHF operation fRF=360 MHz asymmetrical output
UHF operation fRF=360 MHz asymmetrical output
UHF operation fRF=800 MHz asymmetrical output
VHF operation fD=55 MHz fUD=±12 MHz
asymmetrical output
VHF operation fD=360 MHz fUD=±12 MHz
asymmetrical output
UHF operation fD=360 MHz fUD=±12 MHz
asymmetrical output
UHF operation fD=800 MHz fUD=±12 MHz
asymmetrical output

50 Ω load, asymmetrical output
VHF operation fOSC=100 MHz

VHF operation fOSC=405 MHz
UHF operation fOSC=405 MHz
UHF operation fOSC=845 MHz
VHF operation fOSC=100 MHz
VHF operation fOSC=405 MHz
UHF operation fOSC=405 MHz
UHF operation fOSC=845 MHz
VHF operation
UHF operation

Min. Typ. Max. Unit

32 43 52 mA
35 46 55 mA
33 44 53 mA
36 47 56 mA
22 25 28 dB
22 25 28 dB
27 30 33 dB
27 30 33 dB
26 29 32 dB
26 29 32 dB
31 34 37 dB
31 34 37 dB

11 15 dB
11 15 dB

9 12 dB

9.5 12.5 dB

96 100 dBµ

96 100 dBµ

90 94 dBµ

90 94 dBµ

+10 dBm

±300 kHz
±400 kHz
±400 kHz
±400 kHz
±200 kHz
±250 kHz
±250 kHz

±250 kHz
0 0.5 V
3 5.5 V

∗1

Input level –40 dBm, Value measured with untuned input.

∗2

Noise figure is the NF meter direct-reading value (DSB measurement).

∗3

Value with a desired reception signal input level of –30 dBm, an interference signal of 100 kHz at ±12 MHz
: 30 % AM, and an interference signal level where S/I=46 dB measured with a spectrum analyzer.

∗4

Frequency variation from 3 seconds to 3 minutes after switch ON.

∗5

Frequency variation when VCC=5 V ±5 % variation.

∗6

Value which is measured as 410 Ω load impedance and compensated loss by 180 Ω resistor connected to
Pins 15 and 16.

—6—

CXA3125N

Electrical Characteristics Measurement Circuit 1 (asymmetrical output)

IFout1

IFout2

UOSC2

BSW

UOSC1

VOSC2

IFSW

VOSC1

V

CC

MIXout1

MIXout2

GND

VHFin1

VHFin2

UHFin1

UHFin2

CXA3125N

IF OUT

1n

1n

56p

10k

56p

47k

47k

8p

1T363

2.6φ2.5t

0.5p

0.5p

1T363

47k

BAND SW
ON : UHF
OFF : VHF

+5V

1p (UK)

47k

47k

1T362

16p

20

0.5p (UK)

1T363

47k

68p (RH)

3.2φ

2.5t

1n

47k

51

3.2φ

6.5t

51

VL

VH

1n

1n

1.2k

1n3.3µ

Vt

+5V

2k

L1

56p 56p

100

1n

1n

3.3µ

+5V

1n 1n

1n 1n

VHF IN UHF IN

1 2 6 7 83 4 5

15 14 12 11 10

9

16 13

1n

L1 is a pentagonal coil 4.5 t/4.5 t
L without indication is an air-core coil of 0.5 mm diameter.

These components value are the setting for USA frequency variation range.

—7—

CXA3125N

Electrical Characteristics Measurement Circuit 2 (symmetrical output)

IFout1

IFout2

UOSC2

BSW

UOSC1

VOSC2

IFSW

VOSC1

V

CC

MIXout1

MIXout2

GND

VHFin1

VHFin2

UHFin1

UHFin2

CXA3125N

IF OUT

1n

1n

56p

10k

56p

47k

47k

8p

1T363

2.6φ2.5t

0.5p

0.5p

1T363

47k

BAND SW
ON : UHF
OFF : VHF

+5V

1p (UK)

47k

47k

1T362

16p

20

0.5p (UK)

1T363

47k

68p (RH)

3.2φ

2.5t

1n

47k

51

3.2φ

6.5t

51

VL

VH

1n

1n

1.2k

1n3.3µ

Vt

+5V

2k

L1

56p 56p

100

1n

1n

3.3µ

+5V

1n 1n

1n 1n

VHF IN UHF IN

1 2 6 7 83 4 5

1n

180

180

15 14 12 11 10

9

16 13

L1 is a pentagonal coil 4.5 t/4.5 t
L without indication is an air-core coil of 0.5 mm diameter.

These components value are the setting for USA frequency variation range.

—8—

CXA3125N

Description of Operation

(See the Electrical Characteristics Measurement Circuit.)

VHF oscillator circuit

This circuit is a differential amplifier type oscillator circuit. Pin 11 is the output and Pin 9 is the input.
Oscillation is performed by connecting an LC resonance circuit including a varicap to Pin 11 via coupled
capacitance, inputting to Pin 9 with feedback capacitance, and applying positive feedback.
Note that if the capacitance across Pins 9 and 11 is too large, positive feedback may be applied via a
parasitic capacitance causing undesired stray oscillation.

VHF mixer circuit

The mixer circuit employs a double symmetrical mixer with little local oscillation signal leakage. The RF
signal is input to Pins 6 and 7. During normal use, the RF signal is input to one pin while the other pin is
connected to GND. The RF signal is converted to IF frequency by the signal supplied from the oscillator and
then output to Pins 2 and 3. Pins 2 and 3 are open collectors, so power must be supplied externally.
Connect to VCC through L which configures external filter or resistor. The electric potential of Pins 2 and 3 at
this time must be DC 4.0 V or more.

UHF oscillator circuit

This oscillator circuit is designed so that two collector ground type Colpitts oscillators perform differential
oscillation operation via an LC resonance circuit including a varicap. Feedback capacitance is built into IC,
and an LC resonance circuit including a varicap is connected between Pins 12 and 14 via coupled
capacitance.

UHF mixer circuit

This circuit employs a double symmetrical mixer like the VHF mixer circuit. The RF signal is input to Pins 7
and 8. There is a symmetrical input at the differential from both edges of the secondary coil of the pre-stage
double-tuned circuits, or an asymmetrical input to Pin 7 with a capacitor connected at Pin 8 to GND.
Otherwise, the conditions and usage are the same as those for the VHF mixer circuit.

IF amplifier circuit

The signals frequency converted by the mixer are output from Pins 2 and 3, and at the same time are AC
coupled inside the IC and input to the IF amplifier. Single-tuned filters are connected to Pins 2 and 3 in order
to improve the interference characteristics of the IF amplifier.
The signal amplified by the IF amplifier is output with symmetrical or asymmetrical output format. Selecting
symmetrical or asymmetrical is performed at Pin 10. Asymmetrical output when Pin 10 is for open state;
symmetrical output when connected to GND. During symmetrical output, SAW filter direct connection is
possible and during asymmetrical output, output stage drive capability is increased to drive 75 Ω load.
During asymmetrical output, output is performed from Pin 16, and during symmetrical output, output is
performed from Pins 15 and 16. The output impedance is approximately 35 Ω for symmetrical output; 30 Ω
for asymmetrical output. When asymmetrical output is selected, connect Pin 10 to GND through capacitor.

U/V switch circuit

UHF operation is chosen by applying voltage of 3 V or more to Pin 13 VHF operation for 0 V or open.

—9—

CXA3125N

Notes on Operation

1. Care should be taken for grounding, etc. when placing external parts as high operating frequencies are
present.

2. The GND pattern also serves as heat dissipation pins, care should be taken to prevent heat problems.

3. Care should also be taken to prevent electrostatic damage because of using high frequency process.

—10—

CXA3125N

Example of Representative Characteristics

100

DRIFT [kHz]

Supply voltage vs. Circuit current

(for asymmetrical output)

I

CC

- Circuit current [mA]

VCC - Supply voltage [V]

Reception frequency vs. Conversion gain

(for asymmetrical output)

CG - Conversion gain [dB]

Reception frequency [MHz]

Reception frequency vs. Noise figure

(untuned input, for asymmetrical output, DSB display)

NF - Noise figure [dB]

Reception frequency [MHz]

15

10

5

0

Reception frequency vs. +B drift

Reception frequency [MHz]

Reception frequency vs. Next adjacent cross modulation

(untuned input, for asymmetrical output)

CM - Cross modulation [dBµ]

Reception frequency [MHz]

120

100

80

60

40

20

0 200 300 400 500 600 700 800 900100

I/O characteristics (untuned input, for asymmetrical output)

IF output level [dBm]

RF input level [dBm]

54

44

34

4 5 6

: VHF
: UHF

VHF

UHF

fIF=45MHz

40

30

25

20

15

10

5

0

100 200 300 400 500 600 700 800 900

VHF

UHF

fIF=45MHz

200 300 400 500 600 700 800 900

400

200

0

–200

–400

0 200 400 600 800 1000

f

IF=45MHz 100kHz 30% AM

fUD=fD+12MHz
fUD=fD–12MHz

20

0

–20

–40

–60

f

RF=100MHz (VHF)

fRF=450MHz (UHF)
fIF is both f=45 MHz.

–60 –40 –20 0

—11—

CXA3125N

50MHz

0

50

j100

j50

j25

–j50

–j25 –j100

1000p

S11

VHFin1

VHFin2

350MHz

5 6

0

50

j100

j50

j25

–j50

–j25 –j100

1000p

S11

UHFin1

UHFin2

350MHz

7 8

800MHz

VHF Input Impedance

UHF Input Impedance

—12—

CXA3125N

0

50

j100

j50

j25

–j50

–j25 –j100

45MHz

38MHz

0

50

j100

j50

j25

–j50

–j25 –j100

45MHz

38MHz

IF Output Impedance (symmetrical output)

IF Output Impedance (asymmetrical output)

16PIN SSOP (PLASTIC)

SONY CODE
EIAJ CODE
JEDEC CODE

PACKAGE STRUCTURE

PACKAGE MATERIAL
LEAD TREATMENT
LEAD MATERIAL
PACKAGE MASS

EPOXY RESIN
SOLDER / PALLADIUM

42/COPPER ALLOY

0.1g

SSOP-16P-L01
SSOP016-P-0044

∗5.0 ± 0.1

0.65

0.22 – 0.05

+ 0.1

8

1

9

16

∗4.4 ± 0.1

6.4 ± 0.2

0.1 ± 0.1

0.5 ± 0.2

0° to 10°

0.15 – 0.02

+ 0.05

1.25 – 0.1

+ 0.2

A

DETAIL A

0.1

PLATING

NOTE: Dimension “∗” does not include mold protrusion.

0.13

M

Package Outline Unit : mm

CXA3125N

—13—