STV5728

4-HEAD VIDEO AND 2-HEADS HIFI AUDIO

PLAYBACK AND RECORD AMPLIFIER FOR VCR

May 1997

SO28

(Plastic Package)

ORDER CODE : STV5728

ONE 5V POWER SUPPLY

PLAYBACK/RECORD

MODE

SELECTION

THROUGH A LOGIC INPUT

PINNING COMPATIBLE WITH STV5725 AND
STV5727

SO28 PACKAGE

PLAYBACK MODE

LOW NOISE AND WIDE BAND AMPLIFIERS
FOR 4 VIDEO HEADS

AUTOMATIC

OFFSET

CANCELLATION

BETWEEN THE 2 SELECTED HEADS

ONE PLAYBACK OUTPUT WITH AGC

ONE PLAYBACK OUTPUT (60dB CONSTANT
GAIN)

ONE OUTPUT FOR AUTOMATIC VIDEO
TRACKING

SP/LP ENVELOPE COMPARATOR OUTPUT

LOW NOISE AMPLIFIERS FOR 2 HIFI HEADS

HIFI OUTPUT GAIN (70dB)

RECORD MODE

TRANSCONDUCTANCE

AMPLIFIER

FOR

VIDEO

AGC AMPLIFIER FOR HIFI

DESCRIPTION

STV5728 is intended for 4 heads VCR applications
with HIFI. It includes all the electrical functions nec-
essary to achieveplay-back and record processing.
Record or PlaybackMode can be selected through
SWR Pin. SWH allows to select the video head
input (H1SP or H2SP, H1LP or H2LP), while SWM
will select the mode SP or LP. The SWFMH will
select the FM input heads in Playbackand will mute
the HIFI record amplifier in Record Mode.

Playback Mode (Video)
Signals applied on H1SP, H2SP, H1LP and H2LP
input pins will be amplified by 60dB voltage gain.
I

OUTSP

and I

OUTLP

Pins are AC short-circuited to

ground. The input signal can be selected through
SWH and SWM inputs and the corresponding out-
put signal will be available on Pin CPB. The offset

voltage between the two selected heads is auto-
matically cancelled after 32 switching head cycles.
A constant output signal will be available on Pin
YPB thanks to an AGC function (Automatic Gain
Control). The time constant of the AGC is deter-
mined by the capacitor value connected to CAGC
Pin. For Automatic Tracking, a signal which is a
function of the selected input signal amplitude is
present on Pin TRIV. For Trick Mode, a signal
resulting from the comparison of the input signal
amplitude is available on ENVC Pin.

OUTLP

SWR

SWIN

RECIN

CPB

TRIV

ENV

CAGC

H1SP

GNDSP

H2SP

H2LP

CCOM

OUTSP

GNDLP

CCOM2

H1LP

GND

YPB

OUTFM

H1FM

GNDFM

H2FM

FMPB

SWFMH

CCFM

FMRIN

-
0

.
E

PIN CONNECTIONS

1/11

Record Mode (Video)

The current input applied on RECIN Pin is amplified
througha transconductanceamplifier. Special care
has been taken to speed up commutation from
Playback to Record and from Record to Playback,
avoiding spikes through the loads (the rotary trans-
formers). The recording current level in LP mode is
0.9 time the value of SP one.

Playback Mode (FM HIFI)

Signals applied on H1FM and H2FM input Pins will
be amplified by 70dB voltage gain. I

OUTFM

Pin is

AC short-circuited to ground by CCOM1. The input
signal can be selected through SWFMH input and
the correspondingoutput signal will be available on
Pin FMPB.

Record Mode (HIFI)

The current input applied on FMRIN Pin is amplified
through an Automatic Gain Control amplifier. The
recording level can be adjusted thanks to the R

ADJ

resistance connected to TRIV Pin. Special care has
been taken to speedup commutation fromPlayback
to Record and from Record to Playback, avoiding
spikes through the loads (the rotary transformers).

60dB

De tector

Re cord
Amplifica tor

STV5728

H1SP

H2SP

S P HEADS

CCOM

SWR

SWH

SWM

YREC

CREC

CPB

YPB

TRIV (ATR)

+5V

Rrcy

Rrcc

REC

H2LP

H1LP

H1SP

H2SP

H2LP

H1LP

LP HEADS

60dB

Playba ck
AGC

CAGC

ENV
Enve lope Comp

8.2k

22k

CCOM2

H1FM

H2FM

70dB

HIFI HEADS

Re cord Re ference

Current (FM)

ADJ

FMREC

Rfmin

FMPB

SWFMH

CCFM

+5V

Re cord AGC

H1FM

OFF

H2FM

REC MUTE

-
0

.
E

BLOCK DIAGRAM

FUNCTIONAL DESCRIPTION

STV5728

2/11

Current

(mA

)

ADJ

Value (k

)

Recording Level

728-

03.

Figure 1 : FM Record Current Amplifier ; Record Current Adjustment Curve

A certain ratio must be kept between R

ADJ

and

FMIN

to insure maximum performances with an

average FM recording input voltage arou nd
170mV

. Some examples are given in the follow-

ing tables. If the average input voltage is higher (or
lower), the R

FMRIN

value must be increased (de-

creased) proportionnaly.

SET-UP

ADJ

FMRIN

(1)

15k

(2)

22k

1.5k

(3)

33k

ABSOLUTE MAXIMUM RATINGS

Symbol

Parameter

Value

Unit

Power Supply Voltage

Junction Temperature

150

oper

Operating Temperature

0, +70

5728

-
0

.
T

THERMAL DATA

Symbol

Parameter

Value

Unit

th (j-a)

Junction-ambient Thermal Resistance
(IC solded on the PC board)

Max.

C/W

728-

02.

RECOMMENDED OPERATING CHARACTERISTICS

Symbol

Parameter

Min.

Typ.

Max.

Unit

Power Supply

4.75

5.25

CCFM

FM HIFI Power Supply

4.75

5.25

CAGC

AGC Time Constant

4.7

CCOM

Decoupling Capacitor

4.7

470

CCOM1

Decoupling Capacitor

4.7

470

ADJ

Record Current Adjustment Resistor

728-

03.

STV5728

3/11

ELECTRICAL CHARACTERISTICS (T

amb

= 25

C, unless otherwise specified)

Playback Mode
V

= 5V, no load on YPB and CPB Pins, R

ADJ

= 22k

, after 32 SWH (SWitching Head) cycles.

Symbol

Parameter

Test Conditions

Min.

Typ. Max.

Unit

PLAYBACK AMPLIFIER

CC1

Supply Current

GPB

Playback Gain

Sinewave 600kHz, 0.4mV

on inputs

Equivalent Voltage Noise

Input grounded via I

OUT

Pin @ 600kHz,

BW = 10kHz

0.5

0.6

0.7

Equivalent Input Current

Input open @ 6MHz, BW = 10kHz

1.4

2.6

CRT1

Crosstalk Between SP Channels
(or LP Channels)

Sinewave @ 4MHz, 0.4mV

-41

-39

CRT2

Crosstalk

Sinewave @ 600kHz, 0.4mV

-50

CRT3

Crosstalk Between SP1 and LP2
Channels (or SP2 to LP1 Channels)

Sinewave @ 6MHz, 0.4mV

-60

-50

RPBSW

Playback Switch on Resistor

@ 6MHz

0.8

2.5

BWLCF

Attenuation @ 100kHz

Reference level @ 600kHz

-1

BWHCF

Attenuation @ 8MHz

Reference level @ 4MHz

-3

Input Capacitance

@ 6MHz

Input Resistance

@ 6MHz

500

730

950

ZCPB

Output Resistance

VDCPB1

DC Level on Pin CPB

1.35

1.75

2.15

DVDC

Head Switch Offset

-200

200

SHPB1

2nd Harmonic

Sinuswave @ 4MHz, 0.4mV

-43

-37

PLAYBACK AGC FUNCTION

ZYPB

Output Impedance @ YPB

VDCPB2

DC Level @ YPB

1.15

1.45

1.85

BWLCF2

Attenuation @ 100kHz

Reference @ 4MHz, PB AGC locked

-1

BWHCF2

Attenuation @ 8MHz

Reference @ 4MHz, PB AGC locked

-3

-1

VLPB

Output Amplitude

Sinuswave @ 4MHz, 0.4mV

on input

160

200

250

SHPB2

Second Harmonic

Sinuswave @ 4MHz, 0.4mV

on input

-44

-40

IPB+

CAGC Sink Current

100

150

�

IPB-

CAGC Source Current

-150

-100

-50

�

DVLP

AGC Sensitivity

Sinuswave @ 4MHz, 0.2mV

on input,

-5dB and +6dB

-1

TRIV FUNCTION

VTRIV0

Output Level (1)

SP mode, V

cpb

= 0mV

@ 4MHz

0.05

0.28

0.7

VTRIV4

Output Level (4)

LP mode, V

cpb

= 600mV

@ 4MHz

4.1

VTRIV5

Output Level (5)

SP mode, V

cpb

= 100mV

@ 4MHz

1.33

VTRIV6

Output Level (6)

SP mode, V

cpb

= 200mV

@ 4MHz

2.27

VTRIV7

Output Level (7)

LP mode, V

cpb

= 100mV

@ 4MHz

1.4

1.8

2.2

VTRIV8

Output Level (8)

LP mode, V

cpb

= 200mV

@ 4MHz

3.11

VTRIV9

Output Level (9)

SP mode, V

cpb

= 300mV

@ 4MHz

2.95

VTRIV10

Output Level (10)

SP mode, V

cpb

= 600mV

@ 4MHz

3.85

FTRIV1

Response Lower Frequency,
Attenuation @ 1MHz

Reference : SP mode, V

cpb

= 100mV

@ 4MHz

-6

FTRIV2

Response Higher Frequency,
Attenuation @ 8MHz

Reference : SP mode, V

cpb

= 100mV

@ 4MHz

-1

572

.
T

STV5728

4/11

ELECTRICAL CHARACTERISTICS (T

amb

= 25

C, unless otherwise specified) (continued)

Playback Mode (continued)
V

= 5V, no load on YPB and CPB Pins, R

ADJ

= 22k

Symbol

Parameter

Test Conditions

Min.

Typ. Max.

Unit

SP/LP ENVELOPE DETECTOR

Output Resistance @ ENVC

Sinewave 600

�

@ 4 MHz on H2SP

0.65

1.6

2.8

Output Resistance @ ENVC

Sinewave 600

�

@ 4 MHz on H1LP

0.65

1.6

2.8

VENVCH

Output Level

VENVCL

Output Level

SENS1

Sensibility

100

�

to 600

�

@ LP input pins

SENS2

Sensibility

100

�

to 600

�

@ SP input pins

PLAYBACK AMPLIFIER (HIFI)

CCFM1

Supply Current

GPBFM

Playback Gain

Sinewave 1.6MHz, 0.2mV

on inputs

ENFM

Equivalent Voltage Noise

Input grounded via I

OUT

@ 600kHz, BW = 10kHz

0.4

0.5

0.6

INFM

Equivalent Input Current

Input open @ 1.6MHz, BW = 10kHz

2.4

3.5

CRTFM1

Crosstalk

Sinewave @ 1.6MHz, 0.2mV

-45

-40

RPBFMSW

Playback Switch on Resistor

@ 6MHz

1.1

2.4

BWFMLCF

Attenuation @ 1MHz

Reference level @ 1.6MHz

-1

BWFMHCF

Attenuation @ 2MHz

Reference level @ 1.6MHz

-1

INFM

Input Capacitance

@ 1.6MHz

INFM

Input Resistance

@ 1.6MHz

100

550

1000

ZCPBFM

Output Resistance

VDCPBFM

DC Level on Pin YFMPB

1.4

1.8

2.5

DVDCFM

Head Switch Offset

-200

200

SHPBFM1

2nd Harmonic

Sinuswave @ 1.6MHz, 0.2mV

-45

-40

VMAXFM

Maximum Output Voltage

Sinuswave @ 1.6MHz, 2nd harmonic
< -35dB

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05.

STV5728

5/11

Электронный компонент: STV5728