June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

FEATURES

Low voltage (8 V)

Low power dissipation (250 mW)

Automatic standard recognition

No adjustments required

Reduced external components

Not all time constants integrated
(ACC, SECAM de-emphasis).

GENERAL DESCRIPTION

The TDA4657 is a monolithic integrated multi-standard
colour decoder for PAL, SECAM and NTSC 4.43 MHz with
negative colour difference output signals. It is adapted to
the integrated baseband delay line TDA4660/61.

QUICK REFERENCE DATA

Notes to the quick reference data

Within 2 dB output voltage deviation.

2. Burstkey width 4.3

Burst width 2.25

ratio burst chrominance amplitude 1/2.2.

ORDERING INFORMATION

Note

1. SOT146-1; 1996 November 26.

2. SOT163-1; 1996 November 26.

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP. MAX.

UNIT

Supply

supply voltage

7.2

8.0

8.8

supply current

= 8.0 V; without load

tot

total power dissipation

= 8.0 V; without load

248

296

Inputs

chrominance input voltage
(peak-to-peak value)

note 1

200

400

sandcastle input voltage

13.2

Outputs

colour difference output signals
(peak-to-peak value)

independent of supply voltage; note 2

Y) output PAL and NTSC 4.43 MHz

442

525

624

SECAM

950

1050 1150

Y) output PAL and NTSC 4.43 MHz

559

665

791

SECAM

1200

1330 1460

EXTENDED

TYPE NUMBER

PACKAGE

PINS

PIN POSITION

MATERIAL

CODE

TDA4657

DIL

plastic

SOT146

(1)

TDA4657T

plastic

SOT163A

(2)

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

PINNING

SYMBOL

PIN

DESCRIPTION

colour difference signal output

Y)* for baseband delay line

DEEM

external capacitor for SECAM de-emphasis

colour difference signal output

Y)* for baseband delay line

CFOB

external capacitor SECAM demodulator control (B

Y) Channel

GND

ground

REF

external resistor for SECAM oscillator

supply 8 V

CFOR

external capacitor SECAM demodulator control (R

Y) Channel

CHR

chrominance signal input

ACC

external capacitor for ACC control

HUE

input for HUE control and service switch

IDT

external capacitor for identification circuit (NTSC)

IDT

external capacitor for identification circuit (PAL and SECAM)

OSC

PAL crystal

PLL

external loop filter

2FSC

output

standard setting input/output for NTSC 4.43

SEC

standard setting input/output for SECAM

PAL

standard setting input/output for PAL

sandcastle input

Fig.2 Pin configuration.

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

FUNCTIONAL DESCRIPTION

The IC contains all functions required for the identification
and demodulation of signals with the standards PAL,
SECAM and NTSC 4.3 with 4.43 MHz colour-carrier
frequency. When an unknown signal is fed into the input,
the circuit has to detect the standard of the signal, and has
to switch on successively the appropriate input filter and
demodulator and finally, after having identified the signal,
it has to switch on the colour and, in event of NTSC
reception, the hue control. At the outputs the two colour
difference signals

Y)* and

Y)* are available.

ACC stage

The chrominance signal is fed into the asymmetrical input
(pin 9) of the ACC stage (Automatic Colour Control). The
input has to be AC coupled and has an input impedance of
20 k

in parallel with 10 pF.

To control the chrominance amplitude the modulation
independent burst amplitude is measured during the
burstkey pulse which is derived from the sandcastle pulse
present at pin 20. The generated error current is fed into
an external storage capacitor at pin 10. The integrated
error voltage controls the gain of the ACC stage so that its
output is independent of input signal variations.
The measurement is disabled during the vertical blanking
to avoid failures because of missing burst signals.

Reference signal generation

The reference signal generation is achieved by a PLL
system. The reference oscillator operates at twice the
colour-carrier frequency and is locked on the burst of the
chrominance signal (chr). A divider provides reference
signals (f

) with the correct phase relationship for the

PAL/NTSC demodulator and the identification part. In the
SECAM mode the two f

frequencies are derived from the

PAL crystal frequency by special dividers. In this mode the
oscillator is not locked to the input signal. In the NTSC
mode the hue control circuit is switched between ACC
stage and PLL. The phase shift of the signal can be
controlled by a DC voltage at pin 11. The hue control circuit
is switched off during scanning.
The reference frequency (2

) is available at pin 16 to

drive a PAL comb filter for example.

Demodulation

The demodulation of the colour signal requires two
demodulators. One is common for PAL and NTSC signals,
the other is for SECAM signals.
The PAL/NTSC demodulator consists of two synchronized
demodulators, one for the (B

Y) Channel and the other for

the (R

Y) Channel. The required reference signals (f

)

are input from the reference oscillator. In NTSC mode the
PAL switch is disabled.
The SECAM demodulator consists of a PLL system.
During vertical blanking the PLL oscillator is tuned to the
f

frequencies to provide a fixed black level at the

demodulator output. During demodulation the control
voltages are stored in the external capacitors at pins 4
and 8.
The oscillator requires an external resistor at pin 6. Behind
the PLL demodulator the signal is fed into the de-emphasis
network which consists of two internal resistors
(2.8 k

and 5.6 k

) and an external capacitor connected

at pin 2 (220 pF).
After demodulation the signal is filtered and then fed into
the next stage.

Blanking, colour killer, buffers

As a result of using only one demodulator in SECAM mode
the demodulated signal has to be split up in the (B

Channel and the (R

Y) Channel. The unwanted signals

occurring every second line, (R

Y) in the (B

Y) Channel

and (B

Y) in the (R

Y) Channel, have to be blanked. This

happens in the blanking stage by an artificial black level
being inserted alternately every second line.
To avoid disturbances during line and field flyback these
parts of the colour differential signals are blanked in all
modes.
When no signal has been identified, the colour is switched
off (signals are blanked) by the colour killer.
At the end of the colour channels are low-ohmic buffers
(emitter followers). The CD output signals

Y)* and

Y)* are available at pins 1 and 3.

Identification and system control

The identification part contains three identification
demodulators.
The first demodulates in PAL mode. It is only active during
the burstkey pulse. The reference signal (f

) has the

Y) phase.

The second demodulator (PLL system) operates in
SECAM mode and is active also during the burstkey pulse,
but delayed by 2

The PLL demodulator discriminates the frequency
difference between the unmodulated f

frequencies of the

incoming signal (chr) and the reference frequency input
from the crystal oscillator.
These two demodulators are followed by an H/2 switch
`rectifying' the demodulated signal. The result is an
identification signal (P

IDT

, pin 13) that is positive for a PAL

signal in PAL mode, for a SECAM signal in SECAM mode

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

and for a PAL signal in NTSC 4.4 mode. If P

IDT

is positive

in SECAM mode, the scanner switches back to the PAL
mode in order to prevent a PAL signal being erroneously
identified as a SECAM signal (PAL priority).
If then P

IDT

is not positive, the scanner returns to SECAM

mode and remains there if P

IDT

is positive again. In the

event of a field frequency of 60 Hz the signal can not be
identified as a SECAM signal, even if P

IDT

is positive. In

this event the scanner switches forward in the NTSC 4.4
mode. If the H/2 signal has the wrong polarity, the
identification signal is negative and the H/2 flip-flop is set
to the correct phase.
The third demodulator operates in NTSC mode and is
active during the burstkey pulse. The resulting
identification signal (N

IDT

, pin 12) is positive for PAL and

NTSC 4.4 signals in NTSC 4.4 mode. The reference signal
has the (B

Y) phase.

The two identification signals allow an unequivocal
identification of the received signal. In the event of a signal
being identified, the scanning is stopped and after a delay
time the colour is switched on.
The standard outputs (active HIGH) are available at the

pins 17, 18 and 19. During scanning the HIGH level is
2.5 V and when a signal has been identified the HIGH level
is switched to 6 V. The standard pins can also be used as
inputs in order to force the IC into a desired mode (Forced
Standard Setting).

Sandcastle detector and pulse processing

In the sandcastle detector the super sandcastle pulse (SC)
present at pin 20 is compared with three internal threshold
levels by means of three differential amplifiers. The
derived signals are the burstkey pulse, the horizontal
blanking pulse and the combined horizontal and vertical
blanking pulse. These signals are processed into various
control pulses required for the timing of the IC.

Bandgap reference

In order to ensure that the CD output signals and the
threshold levels of the sandcastle detector are
independent of supply voltage variations a bandgap
reference voltage has been integrated.

LIMITING VALUES

In accordance with the Absolute Maximum Rating System (IEC 134).

THERMAL RESISTANCE

SYMBOL

PARAMETER

CONDITIONS

MIN.

MAX.

UNIT

stg

storage temperature

150

amb

operating ambient temperature

supply voltage

8.8

tot

power dissipation

without load

330

voltage at pin 20

max

= 10

voltage at all other pins

max

= 100

SYMBOL

PARAMETER

THERMAL RESISTANCE

th j-a

thermal resistance on printed-circuit board from junction to
ambient in free air (without heat spreader)

SO 20

90 K/W

DIL 20

70 K/W

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

CHARACTERISTICS

Measured with application circuit (Fig.4) at T

amb

= +25

C, 8 V supply, 75% colour bar chrominance input signal of

200 mV (peak-to-peak value) and nominal phase for NTSC unless otherwise specified. All voltages measured
referenced to ground.

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

supply voltage

7.2

8.0

8.8

supply current

= 8.0 V without

load

tot

total power dissipation

= 8.0 V without

load

248

296

CD signals outputs (pins 1 and 3)

PAL or NTSC

colour difference output signals

independent of supply voltage; note 1

Y) output PAL and NTSC 4.43 MHz

(peak-to-peak value)

442

525

624

Y) output PAL and NTSC 4.43 MHz

(peak-to-peak value)

559

665

791

ratio of CD signal amplitudes
V(R

Y)/V(B

note 2

0.75

0.79

0.83

signal linearity

Y) output

= 0.8 V (p-p)

0.8

signal linearity

Y) output

= 1.0 V (p-p)

0.8

cut-off frequency (both outputs)

3 dB

MHz

chrominance delay time

220

270

320

S/N

signal to noise ratio for nominal output
voltages

note 3

, V

residual carrier at CD outputs
1

subcarrier frequency

(peak-to-peak value)

subcarrier frequency

(peak-to-peak value)

H/2 content at R

Y output at nominal input

signal (peak-to-peak value)

crosstalk between CD Channels

, R

output resistance (npn emitter follower)

200

, I

output current

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

SECAM

colour difference output signals

independent of supply voltage; note 4

Y) output (peak-to-peak value)

0.95

1.05

1.15

Y) output (peak-to-peak value)

1.20

1.33

1.46

ratio of CD signal amplitudes
V(R

Y)/V(B

0.75

0.79

0.83

signal linearity at nominal output voltage

0.8

cut-off frequency

3 dB

730

kHz

chrominance delay time

400

500

600

S/N

signal to noise ratio for 100 mV (p-p) input
signal and nominal output voltages

note 3

, V

residual carrier at CD outputs:
1

subcarrier frequency

(peak-to-peak value)

subcarrier frequency

(peak-to-peak value)

shift of demodulated f

level relative to

blanking level

Y) output

note 8

Y) output

Impedance and currents see PAL or NTSC specification

Capacitor for SECAM de-emphasis (pin 2)

value of external capacitor

220

value of internal de-emphasis resistors

amb

= 35

2.4

2.8

3.2

4.8

5.6

6.4

)

relative tolerance of de-emphasis resistors

Capacitors for SECAM demodulator control (pins 4 and 8; note 5)

1, 3

shift of demodulated f

level due to

external leakage current

ext

= 220 nF

0.3

mV/nA

Resistor for SECAM oscillator (pin 6)

DC voltage

2.4

2.81

3.2

value of external resistor (

1%)

5.62

value of external capacitor (

20%)

Chrominance input (pin 9)

input signal (peak-to-peak value)

note 6

200

400

input resistance

input capacitance

Capacitor for ACC (pin 10; note 7)

1, 3

change of CD output signals during field
blanking due to external leakage current

ext

= 100 nF

0.2

%/nA

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

Hue control (NTSC) and service switch (pin 11)

phase shift of reference carrier
relative to phase at open-circuit pin 11

= 3 V

degree

= open-circuit

degree

= 5 V

degree

internal bias voltage
(proportional to supply voltage)

pin 11 open-circuit

3.8

4.0

4.2

input resistance

Capacitor for identification (pins 12 and 13)

, V

DC voltage for an identified signal

2.8

3.2

3.5

DC voltage for an unidentified signal

1.5

2.0

2.3

PLL oscillator measured with nominal crystal (pin 14; see Table 1)

initial oscillator amplifier input resistance

500

oscillator amplifier input capacitance

lock-in-range referenced to
4.43361875 MHz

note 9

400

1300

phase difference for

400 Hz deviation of

colour carrier frequency

degree

2 x f

output (pin 16; if the output is not used, the pin should be connected to supply)

DC output level

= 0 A

6.1

6.3

6.5

output resistance

= 0 A

350

output current

1.0

output signal (peak-to-peak value)

250

Standard setting inputs/outputs (pins 17 to 19; note 10)

used as output: npn emitter follower output with 0.1 mA source to ground

on-state, during scanning, colour OFF

2.3

2.5

2.7

on-state, colour ON

5.8

6.0

6.2

output resistance

= 0

300

output current

used as input: forced system switching

threshold for system ON

6.8

7.0

7.2

input current

100

150

180

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

Notes to the characteristics

1. Burstkey width 4.3

Burst width 2.25

s, ratio burst chrominance amplitude 1/2.2.

2. At nominal phase of hue control.

3. V (p-p) of signal divided by 6 times effective noise voltage.

4. H/2 blanking alternately every second line.

5. These pins are leakage current sensitive. Pin 4 for (B

Y) Channel, pin 8 for (R

Y) Channel.

6. Within 2 dB output voltage deviation.

7. This pin is leakage current sensitive.

8. IC only.

9. Depends also on network on pin 15.

10. Pin 19 for PAL, pin 18 for SECAM, pin 17 for NTSC 4.43 MHz.

Threshold levels are dependent of supply.

11. The field interval of the sandcastle has to be adapted to the ICs TDA2579B and TDA4690.

The thresholds are independent of supply voltage.

12. System scanning sequence: PAL, SECAM, NTSC 4.4.

Sandcastle pulse detector (pin 20; note 11)

input capacitance

thresholds for field and line pulse

pulse ON

1.3

1.6

1.9

separation

pulse OFF

1.1

1.4

1.7

line pulse separation

pulse ON

3.3

3.6

3.9

pulse OFF

3.1

3.4

3.7

burst pulse separation

pulse ON

5.3

5.6

5.9

pulse OFF

5.1

5.4

5.7

System control processing (note 12)

system hold delay

in event of a signal
disappearing for a
short time

field
periods

colour killer; colour ON delay

switching occurs
during field blanking

field
periods

colour OFF delay

field
periods

scanning time for each system

field
periods

QUALITY SPECIFICATION: URV-4-2-59/601

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

PACKAGE OUTLINES

UNIT

max.

REFERENCES

OUTLINE

VERSION

EUROPEAN

PROJECTION

ISSUE DATE

IEC

JEDEC

EIAJ

inches

DIMENSIONS (inch dimensions are derived from the original mm dimensions)

SOT146-1

92-11-17
95-05-24

min.

max.

1.73
1.30

0.53
0.38

0.36
0.23

26.92
26.54

6.40
6.22

3.60
3.05

0.254

2.54

7.62

8.25
7.80

10.0

8.3

2.0

4.2

0.51

3.2

0.068
0.051

0.021
0.015

0.014
0.009

1.060
1.045

0.25
0.24

0.14
0.12

0.01

0.10

0.30

0.32
0.31

0.39
0.33

0.078

0.17

0.020

0.13

SC603

(e )

seating plane

pin 1 index

10 mm

scale

Note

1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.

(1)

DIP20: plastic dual in-line package; 20 leads (300 mil)

SOT146-1

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

UNIT

max.

(1)

REFERENCES

OUTLINE

VERSION

EUROPEAN

PROJECTION

ISSUE DATE

IEC

JEDEC

EIAJ

inches

2.65

0.30
0.10

2.45
2.25

0.49
0.36

0.32
0.23

13.0
12.6

7.6
7.4

1.27

10.65
10.00

1.1
1.0

0.9
0.4

8
0

0.25

0.1

DIMENSIONS (inch dimensions are derived from the original mm dimensions)

Note

1. Plastic or metal protrusions of 0.15 mm maximum per side are not included.

1.1
0.4

SOT163-1

detail X

0.25

075E04

MS-013AC

pin 1 index

0.10

0.012
0.004

0.096
0.089

0.019
0.014

0.013
0.009

0.51
0.49

0.30
0.29

0.050

1.4

0.055

0.419
0.394

0.043
0.039

0.035
0.016

0.01

0.25

0.01

0.004

0.043
0.016

0.01

10 mm

scale

(A )

SO20: plastic small outline package; 20 leads; body width 7.5 mm

SOT163-1

95-01-24
97-05-22

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

SOLDERING

Introduction

There is no soldering method that is ideal for all IC
packages. Wave soldering is often preferred when
through-hole and surface mounted components are mixed
on one printed-circuit board. However, wave soldering is
not always suitable for surface mounted ICs, or for
printed-circuits with high population densities. In these
situations reflow soldering is often used.

This text gives a very brief insight to a complex technology.
A more in-depth account of soldering ICs can be found in
our

"IC Package Databook" (order code 9398 652 90011).

DIP

OLDERING BY DIPPING OR BY WAVE

The maximum permissible temperature of the solder is
260

C; solder at this temperature must not be in contact

with the joint for more than 5 seconds. The total contact
time of successive solder waves must not exceed
5 seconds.

The device may be mounted up to the seating plane, but
the temperature of the plastic body must not exceed the
specified maximum storage temperature (T

stg max

). If the

printed-circuit board has been pre-heated, forced cooling
may be necessary immediately after soldering to keep the
temperature within the permissible limit.

EPAIRING SOLDERED JOINTS

Apply a low voltage soldering iron (less than 24 V) to the
lead(s) of the package, below the seating plane or not
more than 2 mm above it. If the temperature of the
soldering iron bit is less than 300

C it may remain in

contact for up to 10 seconds. If the bit temperature is
between 300 and 400

C, contact may be up to 5 seconds.

EFLOW SOLDERING

Reflow soldering techniques are suitable for all SO
packages.

Reflow soldering requires solder paste (a suspension of
fine solder particles, flux and binding agent) to be applied
to the printed-circuit board by screen printing, stencilling or
pressure-syringe dispensing before package placement.

Several techniques exist for reflowing; for example,
thermal conduction by heated belt. Dwell times vary
between 50 and 300 seconds depending on heating

method. Typical reflow temperatures range from
215 to 250

Preheating is necessary to dry the paste and evaporate
the binding agent. Preheating duration: 45 minutes at
45

AVE SOLDERING

Wave soldering techniques can be used for all SO
packages if the following conditions are observed:

A double-wave (a turbulent wave with high upward
pressure followed by a smooth laminar wave) soldering
technique should be used.

The longitudinal axis of the package footprint must be
parallel to the solder flow.

The package footprint must incorporate solder thieves at
the downstream end.

During placement and before soldering, the package must
be fixed with a droplet of adhesive. The adhesive can be
applied by screen printing, pin transfer or syringe
dispensing. The package can be soldered after the
adhesive is cured.

Maximum permissible solder temperature is 260

C, and

maximum duration of package immersion in solder is
10 seconds, if cooled to less than 150

C within

6 seconds. Typical dwell time is 4 seconds at 250

A mildly-activated flux will eliminate the need for removal
of corrosive residues in most applications.

EPAIRING SOLDERED JOINTS

Fix the component by first soldering two diagonally-
opposite end leads. Use only a low voltage soldering iron
(less than 24 V) applied to the flat part of the lead. Contact
time must be limited to 10 seconds at up to 300

C. When

using a dedicated tool, all other leads can be soldered in
one operation within 2 to 5 seconds between
270 and 320

June 1993

Philips Semiconductors

Preliminary specification

Generic multi-standard decoder

TDA4657

DEFINITIONS

LIFE SUPPORT APPLICATIONS

These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be expected to result in personal injury. Philips customers using or selling these products for
use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such
improper use or sale.

Data sheet status

Objective specification

This data sheet contains target or goal specifications for product development.

Preliminary specification

This data sheet contains preliminary data; supplementary data may be published later.

Product specification

This data sheet contains final product specifications.

Limiting values

Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or
more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation
of the device at these or at any other conditions above those given in the Characteristics sections of the specification
is not implied. Exposure to limiting values for extended periods may affect device reliability.

Application information

Where application information is given, it is advisory and does not form part of the specification.

Document Outline

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: TDA4657T

Document Outline

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: TDA4657T