Sanyo EP58B specifications LA75503V, LA75505M, Rf Agc

VIF/SIF Signal-Processing Circuit

LA75503V

Overview

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.

Functions and Features

VIF/SIF Signal-Processing Circuit

LA75505M

Overview

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.

Functions and Features

VIF amplifier	The built-in VCO has been made adjustment free so that VCO coil adjustment
VCO adjustment-free PLL detection circuit	is not required.
Digital AFT circuit	The integration on the same chip of the audio bandpass filter and trap make
RF AGC	implementation of end products that support PAL multisystem audio easy
Buzz canceller	and low cost.
Equalizer amplifier	Achieves a significant reduction in the number of required peripheral
Audio carrier bandpass filter	components
Audio carrier trap	Obviates the problem of AFT tolerances by adopting a digital AFT system
PLL FM detector	Package: SSOP30 (275 mil)
Reference signal generator

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)

Block Diagram

OPEN : PAL

GND : NT

2.2kΩ

10kΩ

IF INPUT

6.8kΩ

0.01∝F

2SC3134

100kΩ

2.2kΩ

VCC(5V)

SAW(S)

30kΩ

0.01∝F

VCC(9V)

0.01∝F

RF AGC OUT

1∝F

3kΩ

1∝F

+ 100∝F

0.022∝F

0.1∝F

+

+

47kΩ

47kΩ

0.01∝F

SAW(P)0.01∝F

10K-B

1000pF

AUDIO OUT

29

27

26

25

24

23

22

21

20

19

18

17

16

AFT OUT

30

28

NE

NE

DEEMPHA

FM

DET

FM

S

VIF

1 st

DET

PLL

AMP

IF

AMP

AGC

AFT

AGC

AMP

FIL

VIDEO

APC

CONT

1 stSIF

LIM

DET

DET

DET

AMP

BPF

AMP

SW

EQ

TRAP

LPF

VCO

FLL

AMP

PAL SW

BPF

VCC : 39.5MHz

NE

NC

OPEN : 38.9MHz

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

GND : 38.0MHz

+

1∝F

+

+

220kΩ

1∝F

2kΩ

1∝F

300kΩ

0.01∝F

3kΩ

A

B

SYSTEM

SW

39pF

39pF

300kΩ

VCO COIL

4MHz X tal

VIDEO OUT

10∝H

Block Diagram

0.01∝F

IF INPUT

IF INPUT

VCC(5V)

SAW(S)

30kΩ

0.01∝F

VCC(9V)

0.01∝F

0.01∝F

RF AGC OUT

AUDIO OUT

+ 100∝F

7.5kΩ

3kΩ

1∝F

0.1∝F

+

47kΩ

47kΩ

SAW(P)

0.01∝F

0.022∝F

10K-B

1000pF

AFT OUT

24

23

22

21

20

19

18

17

16

15

14

13

FM

DET

FM

S

VIF

1 st

DET

PLL

AMP

IF

AMP

AGC

AFT

AGC

AMP

FIL

VIDEO

CONT

DET

APC

1 stSIF

LIM

DET

DET

AMP

BPF

AMP

SW

EQ

TRAP

LPF

VCO

AMP

FLL

BPF

1

2

3

4

5

6

7

8

9

10

11

12

3kΩ

2kΩ

+

+

220kΩ

IF SW

OPEN : 45.75MHz

1∝F

1∝F

GND : 58.75MHz

0.01∝F

+

1∝F

0.01∝F

330kΩ

VCO COIL

4MHz X tal

VIDEO OUT

39pF

CARRIER OUT

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