Vif/sif signal-processing circuit, Overview, Functions and features – Sanyo EP58B User Manual

Page 23

Advertising
background image

LA75503V

43

44

SANYO TV . VCR

SANYO TV . VCR

LA75505M

3k

2k

220k

300k

300k

1

µ

F

0.01

µ

F

39pF

39pF

10

µ

H

+

1

µ

F

+

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

DEEMPHA

FM

DET

LIM

AMP

EQ

AMP

BPF

BPF

S

PLL

FIL

CONT

IF

AGC

FM

DET

AFT
AMP

AMP

SW

TRAP

LPF

VCO

VIDEO

DET

APC
DET

1 stSIF

DET

1 st

AMP

VIF

AMP

FLL

AGC

1

µ

F

+

NC

VIDEO OUT

VCO COIL

A

SYSTEM

B

SW

4MHz X tal

3k

10k

2.2k

30k

47k

47k

2.2k

6.8k

100k

0.01

µ

F

0.01

µ

F

0.01

µ

F

1

µ

F

1000pF

+

PAL SW
VCC : 39.5MHz

OPEN : 38.9MHz
GND : 38.0MHz

1

µ

F

100

µ

F

0.022

µ

F

0.01

µ

F

0.1

µ

F

+

+

AUDIO OUT

10K-B

NE

NE

NE

OPEN : PAL

GND : NT

2SC3134

SAW(P)

0.01

µ

F

IF INPUT

SAW(S)

VCC(5V)

VCC(9V)

RF AGC OUT

AFT OUT

FM

DET

LIM

AMP

BPF

BPF

EQ

AMP

S

PLL

FIL

CONT

IF

AGC

FM

DET

AFT
AMP

AMP

SW

TRAP

LPF

VCO

VIDEO

DET

APC
DET

1 stSIF

DET

1 st

AMP

VIF

AMP

FLL

AGC

3k

2k

220k

330k

1

µ

F

0.01

µ

F

0.01

µ

F

39pF

+

1

µ

F

+

1

µ

F

+

VIDEO OUT

CARRIER OUT

VCO COIL

4MHz X tal

IF SW
OPEN : 45.75MHz
GND : 58.75MHz

3k

7.5k

30k

47k

47k

0.01

µ

F

0.01

µ

F

0.01

µ

F

1000pF

1

µ

F

100

µ

F

0.022

µ

F

0.01

µ

F

0.1

µ

F

+

+

AUDIO OUT

10K-B

SAW(P)

0.01

µ

F

IF INPUT

SAW(S)

VCC(5V)

VCC(9V)

RF AGC OUT

IF INPUT

AFT OUT

24

23

22

21

20

19

18

17

16

15

14

13

1

2

3

4

5

6

7

8

9

10

11

12

Overview

Functions and Features

Overview

Functions and Features

Block Diagram

Block Diagram

VIF/SIF Signal-Processing Circuit

VIF/SIF Signal-Processing Circuit

The LA75503V is a completely adjustment-free PAL VIF/SIF signal-processing IC for TV sets and VCRs.
It supports IF frequencies of 38, 38.9, and 39.5 MHz. It also provides on-chip audio carrier trap, and audio carrier bandpass filters to
support PAL multisystem audio (M/N, B/G, I, and D/K). A reference frequency of 4 MHz is used for the adjustment-free circuits,
and the VCO, AFT, and audio filters are controlled either by a crystal oscillator circuit or an external clock input.

VIF amplifier
VCO adjustment-free PLL detection circuit
Digital AFT circuit
RF AGC
Buzz canceller
Equalizer amplifier
Audio carrier bandpass filter
Audio carrier trap
PLL FM detector
Reference signal generator

The built-in VCO has been made adjustment free so that VCO coil adjustment
is not required.
The integration on the same chip of the audio bandpass filter and trap make
implementation of end products that support PAL multisystem audio easy
and low cost.
Achieves a significant reduction in the number of required peripheral
components
Obviates the problem of AFT tolerances by adopting a digital AFT system
Package: SSOP30 (275 mil)

The LA75505M is a completely adjustment-free NTSC VIF/SIF signal-processing IC for TV sets and VCRs.
It supports IF frequencies of 45.75 and 58.75 MHz.
It integrates both audio carrier trap and audio carrier bandpass filters on chip and thus is optimal for compact light weight tuners.
A reference frequency of 4 MHz is used for the adjustment-free circuits, and the VCO, AFT, and audio filters are controlled either by
a crystal oscillator circuit or an external clock input.

VIF amplifier
VCO adjustment-free PLL detection circuit
Digital AFT circuit
RF AGC
Buzz canceller
Equalizer amplifier
Audio carrier bandpass filter
Audio carrier trap
PLL FM detector
Reference signal generator

The built-in VCO has been made adjustment free so that VCO coil adjustment
is not required.
The integration on the same chip of the audio bandpass filter and trap
significantly reduces the number of required peripheral components for lower
total costs.
Obviates the problem of AFT tolerances by adopting a digital AFT system
Package: MFP24S (300mil)

Advertising