SANYO LA7688 Datasheet

Overview

The LA7688 integrates VIF, SIF, video, chrominance, and
deflection processing circuits for PAL/NTSC format TV
sets on a single chip and is provided in a 52-pin shrink
package.

The VIF and SIF circuits achieve semi-adjustment-free
operation, and are adjustment-free except for the VCO coil
and the RF AGC circuit. The chrominance circuit can be
made adjustment-free by using the LC89950 1H delay line
IC. All the signal processing required for a multi-format
color TV can be implemented by combining this product
with the LA7642 SECAM decoder IC.

Features

[VIF] • PLL detector • Buzz canceller
[SIF] • PLL detector • Audio switch
[VIDEO] • Built-in trap • Built-in DL

• Aperture control

• Video switch (SVO output)

• Black expansion

[CHROMA] • PAL/NT • Base band processing

(adjustment free)

• Built-in bandpass filter

[OSD] • Analog OSD
[DEF] • Automatic 50/60 Hz discrimination

• Fixed vertical size • Double AFC

• Built-in sync separator circuit

[Other features] • Sandcastle pulse (for the 1H delay line)

• fsc output (for SECAM systems)

• Primary color output

Package Dimensions

unit: mm

3218-DIP52S

Monolithic Linear IC

Ordering number : EN5635

82097HA(OT) No. 5635-1/6

SANYO: DIP52S

[LA7688]

SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN

Single-Chip CTV Signal-Processing Circuit

for PAL and NTSC Formats

LA7688

Parameter Symbol Conditions Ratings Unit

Maximum supply voltage

V

40

max 9V

V

45

max 9V

Maximum supply current I

24

max 16 mA

FBP input current

I

26

max 5mA

I

32

max 10 mA

FBP input voltage I

26

min –5 V
Allowable power dissipation Pd max Ta ≤ 65°C When mounted on a printed circuit board* 1.3 W
Operating temperature Topr –10 to +65 °C
Storage temperature Tstg –55 to +150 °C

Specifications

Maximum Ratings at Ta = 25°C

Parameter Symbol Conditions Ratings Unit

Recommended supply voltage

V

40

7.6 V

V

45

7.6 V

Recommended supply current I24 12 mA

Operating voltage range

V

40

op 7 to 8.2 V

V

45

op 7 to 8.2 V

Operating current range I

24

op 10 to 16 mA

Operating Conditions at Ta = 25°C

Note : * Printed circuit board size: 83 × 86 × 1.5 mm, material: Bakelite

No. 5635-2/6

LA7688

Parameter Symbol Conditions

Ratings

Unit

min typ max

[Circuit Voltages and Currents]

Horizontal power-supply voltage V

CC

H Deflection system (V24) 6.4 6.9 7.4 V

Current drain

I

40

78 90 100 mA

I

45

34 40 48 mA

[VIF Block]

RF AGC maximum voltage V

50H

7.5 7.8 7.8 V

RF AGC minimum voltage V

50L

0.2 0.6 V

Input sensitivity V

i

39 45 dBµ
AGC range GR 56 60 dB
Maximum allowable input V

IN max

95 100 dBµ

Quiescent video output voltage V

8

4.1 4.4 4.7 V

Synchronizing signal tip voltage V

8tip

1.7 2.0 2.3 V

Video output amplitude V

O

1.7 2.0 2.3 Vp-p

Black noise threshold voltage V

BTH

1.0 1.3 1.7 V

Black noise clamp voltage V

BCL

2.7 3.0 3.3 V

Output signal-to-noise ratio S/N 48 52 dB

1.07 MHz beat level C/S 40 44 dB
Frequency characteristics f

C

6 9 MHz
Differential gain DG 5 10 %
Differential phase DP 6 10 deg
Quiescent AFT voltage V

7

3.6 3.9 4.2 V

Maximum AFT voltage V

7H

7.3 7.6 7.8 V

Minimum AFT voltage V

7L

0 0.3 0.7 V
AFT detection sensitivity Sf 10 15 20 mV/kHz
VIF input resistance Ri f = 38.9 MHz 1.0 1.3 1.6 kΩ
VIF input capacitance Ci f = 38.9 MHz 2 3 5 pF
APC pull-in range (U) f

PU

0.8 2.0 MHz

APC pull-in range (L) f

PL

–2 –0.8 MHz

VCO1 maximum variation range

∆

fU1

0.8 2.0 MHz

∆

fL1

–2.0 –0.8 MHz

SIF signal level S

OUT

110 140 170 mVrms

VCO1 control sensitivity ß 2.4 4.8 9.6 kHz

[SIF Block]

SIF limiting sensitivity V

i

(lim) 40 46 52 dBµ

FM detector output voltage V

O

(FM) 390 500 710 mVrms
AMR AMR 40 60 dB
Total harmonic distortion THD 0.3 1.0 %
SIF S/N S/N (SIF) 55 62 dB
FM detector range (L) W

FML

2.5 4.0 MHz

FM detector range (H) W

FMH

7.0 8.0 MHz

FM detector output variability ∆V

O

0 2.0 3.0 dB

[INT/EXT Switching Block]

AFT EXT gain G

AF

–0.7 –0.2 +0.3 dB

AFT EXT distortion THD

AF

0.03 0.5 %

System switch I-SE V1

TH1

Notes: 0 1.2 V

System switch I-P/N V1

TH2

I = INT, E = EXT 1.7 2.6 V

System switch E-P/N V1

TH3

P/N = PAL/NTSC 2.9 3.8 V

System switch E-SE V1

TH4

SE = SECAM 4.1 5 V

[Video Switching Block]

Video signal input 1 DC voltage V

10DC

3.2 3.5 3.8 V

Video signal input 1 AC voltage V

10AC

1.0 Vp-p

Video signal input 2 DC voltage V

14DC

3.2 3.5 3.8 V

Video signal input 2 AC voltage V

14AC

1.0 Vp-p

SVO pin DC voltage V

16DC

2.5 2.8 3.1 V

SVO pin AC voltage V

16AC

1.7 2.0 2.3 Vp-p

Operating Characteristics at Ta = 25°C, V

CC40, 45

= 7.8 V, I24= 12 mA

Continued on next page.