SGS Thomson Microelectronics STV5728 Datasheet

4-HEAD VIDEOAND 2-HEADSHIFI AUDIO

PLAYBACKAND RECORD AMPLIFIERFORVCR

.

ONE 5V POWERSUPPLY

.

PLAYBACK/RECORD MODE SELECTION
THROUGH A LOGICINPUT

.

PINNING COMPATIBLE WITH STV5725 AND
STV5727

.

SO28 PACKAGE

PLAYBACK MODE

.

LOW NOISE AND WIDE BAND AMPLIFIERS
FOR4 VIDEOHEADS

.

AUTOMATIC OFFSET CANCELLATION
BETWEENTHE 2 SELECTEDHEADS

.

ONE PLAYBACKOUTPUT WITH AGC

.

ONE PLAYBACKOUTPUT(60dB CONSTANT
GAIN)

.

ONE OUTPUT FOR AUTOMATIC VIDEO
TRACKING

.

SP/LPENVELOPECOMPARATOROUTPUT

.

LOWNOISEAMPLIFIERSFOR 2 HIFIHEADS

.

HIFI OUTPUT GAIN (70dB)

RECORDMODE

.

TRANSCONDUCTANCE AMPLIFIER FOR
VIDEO

.

AGC AMPLIFIER FORHIFI

DESCRIPTION

STV5728is intendedfor4 headsVCR applications
withHIFI.It includesall the electricalfunctionsnec­essaryto achieveplay-backandrecordprocessing.

Recordor PlaybackModecanbe selectedthrough
SWR Pin. SWH allows to select the video head
input(H1SPor H2SP,H1LP or H2LP), whileSWM
will select the mode SP or LP. The SWFMH will
selecttheFMinputheadsin Playbackandwillmute
the HIFI record amplifier in Record Mode.

PlaybackMode (Video)
Signalsapplied on H1SP, H2SP, H1LP and H2LP

input pins will be amplified by 60dB voltage gain.
I
ground. The input signal can be selected through
SWHand SWM inputs and the corresponding out­put signal will be availableon PinCPB. The offset

OUTSP

and I

Pins are AC short-circuited to

OUTLP

STV5728

voltage between the two selected heads is auto­maticallycancelledafter 32 switchinghead 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 deter­mined by the capacitorvalue 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
amplitudeis availableon ENVC Pin.

SO28

(Plastic Package)

ORDER CODE : STV5728

PIN CONNECTIONS

H1SP

GNDSP

H2SP

I

OUTSP

CCOM

I

OUTLP

H2LP

GNDLP

H1LP

CCOM2

I

OUTFM

H1FM

GNDFM

H2FM

1
2
3
4
5
6
7
8
9
10
11
12
13
14

28
27
26
25
24
23
22
21
20
19
18
17
16
15

SWR
SWIN
V

CC

RECIN
CPB
GND
YPB
TRIV

ENV

CAGC

FMRIN
FMPB

SWFMH

V

CCFM

5728-01.EPS

May 1997

1/11

STV5728

BLOCKDIAGRAM

H1SP

H2SP

SP HEADS

CCOM

LP HEADS

H2LP

H1LP

CCOM2

HIFIHEADS

H1FM

60dB

1

2

3

60dB

4

5

6

60dB

7

8

60dB

9

10 19

11

12

Detector

Record Reference

70dB

Current (FM)

Record AGC

REC

PB

H2LP

H1LP
H1SP
H2SP

Record
Amplificator

Playback
AGC

28

27

26

25

24

23

22

21

20

18

17

+5V

CAGC

22k

8.2k

Rrcy

Rrcc

R

ADJ

Rfmin

Ω

Ω

SWR
SWH

SWM
V

CC

YREC

CREC
CPB

YPB

TRIV(ATR)
ENV

Envelope Comp

FMREC

FMPB

13

PB REC MUTE

H2FM

14

70dB

H1FM OFF
H2FM ON

STV5728

FUNCTIONAL DESCRIPTION
RecordMode (Video)

ThecurrentinputappliedonRECINPinis amplified
througha transconductanceamplifier.Specialcare
has been taken to speed up commutation from
Playbackto Record and fromRecordto Playback,
avoidingspikesthroughtheloads (the rotarytrans­formers).The recordingcurrentlevel inLP mode is

0.9 time the valueof SP one.

PlaybackMode (FM HIFI)
Signalsappliedon H1FMand H2FMinput Pinswill

be amplified by 70dB voltage gain. I

2/11

OUTFM

Pin is

16

15

+5V

SWFMH

V

CCFM

AC short-circuitedto groundbyCCOM1. The input
signal can be selected throughSWFMH input and
thecorrespondingoutput signalwill beavailableon
Pin FMPB.

Record Mode (HIFI)
ThecurrentinputappliedonFMRINPinis amplified

through an Automatic Gain Control amplifier. The
recordinglevelcan be adjustedthanks to the R

ADJ

resistanceconnectedtoTRIVPin.Specialcarehas
beentakento speedupcommutationfromPlayback
to Recordand from Record to Playback, avoiding
spikesthroughthe loads (therotarytransformers).

5728-02.EPS

STV5728

ABSOLUTEMAXIMUM RATINGS

Symbol Parameter Value Unit

V

CC

T

T

oper

THERMAL DATA

Symbol Parameter Value Unit

R

th (j-a)

RECOMMENDED OPERATING CHARACTERISTICS

Symbol Parameter Min. Typ. Max. Unit

V

CC

V

CCFM

CAGC AGC Time Constant 4.7 22 nF

CCOM Decoupling Capacitor 4.7 470 nF

CCOM1 Decoupling Capacitor 4.7 470 nF

R

ADJ

Figure 1 : FM RecordCurrentAmplifier; RecordCurrent Adjustment Curve

Power Supply Voltage 6 V
Junction Temperature 150

j

Operating Temperature 0, +70

Junction-ambient Thermal Resistance

Max. 75

(IC solded on the PC board)

Power Supply 4.75 5 5.25 V
FM HIFI Power Supply 4.75 5 5.25 V

Record Current Adjustment Resistor 15 22 33 k

70

o

C/W

o

C

o

C

5728-01.TBL

5728-02.TBL

Ω

5728-03.TBL

60

)

PP

50

40

Current(mA

30

20

10 20 30 40

A certain ratio must be kept between R

to insure maximum performances with an

R

FMIN

ADJ

and

averag e FM recording input voltage around
170mV

. Some examplesare given in the follow-

PP

ingtables.If theaverageinput voltage is higher (or
lower), the R

value must be increased (de-

FMRIN

creased)proportionnaly.

R

ADJ

RecordingLevel

Value(kΩ)

SET-UP R

(1) 15k
(2) 22kΩ 1.5kΩ
(3) 33kΩ 2kΩ

ADJ

5728-03.EPS

R

FMRIN

Ω

1k

Ω

3/11

STV5728

ELECTRICALCHARACTERISTICS (T

=25oC, unless otherwisespecified)

amb

PlaybackMode

= 5V,no loadon YPBand CPBPins, R

V

CC

Symbol Parameter Test Conditions Min. Typ. Max. Unit

PLAYBACK AMPLIFIER

I

CC1

Supply Current 40 48 53 mA

GPB Playback Gain Sinewave 600kHz, 0.4mV

EN Equivalent Voltage Noise

IN Equivalent Input Current Input open @ 6MHz, BW = 10kHz 1.4 2 2.6

CRT1 Crosstalk Between SP Channels

(or LP Channels)

CRT2 Crosstalk Sinewave @ 600kHz, 0.4mV
CRT3

Crosstalk Between SP1and LP2
Channels (or SP2 to LP1 Channels)

RPBSW Playback Switch on Resistor @ 6MHz 0.8 2.5 18

BWLCF Attenuation @ 100kHz Reference level @ 600kHz -1 0 1 dB

BWHCF Attenuation @ 8MHz Reference level @ 4MHz -3 1 0 dB

C
R

Input Capacitance @ 6MHz 22 27 32 pF

IN

Input Resistance @ 6MHz 500 730 950 Ω

IN

ZCPB Output Resistance DC 5 14 50

VDCPB1 DC Levelon Pin CPB 1.35 1.75 2.15 V

DVDC Head Switch Offset -200 0 200 mV

SHPB1 2nd Harmonic Sinuswave @ 4MHz, 0.4mV

PLAYBACK AGC FUNCTION

ZYPB Output Impedance @ YPB 5 14 50 Ω
VDCPB2 DC Level@ YPB 1.15 1.45 1.85 V
BWLCF2 Attenuation @ 100kHz Reference @ 4MHz, PB AGC locked -1 0 1 dB

BWHCF2 Attenuation @ 8MHz Reference @ 4MHz, PB AGC locked -3 -1 1 dB

VLPB Output Amplitude Sinuswave @ 4MHz, 0.4mV

SHPB2 Second Harmonic Sinuswave @ 4MHz, 0.4mVPPon input -44 -40 dB

IPB+ CAGC Sink Current 50 100 150

IPB- CAGC Source Current -150 -100 -50

DVLP AGC Sensitivity

TRIV FUNCTION

VTRIV0 Output Level (1) SP mode, V
VTRIV4 Output Level (4) LP mode, V
VTRIV5 Output Level (5) SP mode, V
VTRIV6 Output Level (6) SP mode, V
VTRIV7 Output Level (7) LP mode, V
VTRIV8 Output Level (8) LP mode, V
VTRIV9 Output Level (9) SP mode, V

VTRIV10 Output Level (10) SP mode, V

FTRIV1

FTRIV2

Response Lower Frequency,
Attenuation @ 1MHz

Response Higher Frequency,
Attenuation @ 8MHz

=22kΩ, after 32 SWH (SWitching Head) cycles.

ADJ

on inputs 58 60 62 dB

PP

Input grounded via I
BW = 10kHz

Sinewave @ 4MHz, 0.4mV

Sinewave @ 6MHz, 0.4mV

Sinuswave @ 4MHz, 0.2mV

-5dB and +6dB

= 0mVPP@ 4MHz 0.05 0.28 0.7 V

cpb

= 600mVPP@ 4MHz 4.1 V

cpb

= 100mVPP@ 4MHz 1.33 V

cpb

= 200mVPP@ 4MHz 2.27 V

cpb

= 100mVPP@ 4MHz 1.4 1.8 2.2 V

cpb

= 200mVPP@ 4MHz 3.11 V

cpb

= 300mVPP@ 4MHz 2.95 V

cpb

= 600mVPP@ 4MHz 3.85 V

cpb

Reference : SP mode, V
@ 4MHz

Reference : SP mode, V
@ 4MHz

Pin @ 600kHz,

OUT

PP

PP

PP

PP

PP

= 100mV

cpb

= 100mV

cpb

0.5 0.6 0.7

PP

on input 160 200 250 mV

on input,

PP

PP

-1 0 1 dB

-41 -39 dB

-50 dB

-60 -50 dB

-43 -37 dB

-6 dB

-1 dB

nV

√Hz

pA

Hz

√

Ω

Ω

µ
µ

PP

A
A

5728-04.TBL

4/11