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July 1992

2

Philips Semiconductors

Preliminary specification

Small signal combination IC for black/white TV

TDA8303

TDA8303A

FEATURES

Video IF amplifier with synchronous demodulator

Automatic gain control (AGC) detector suitable for
negative modulation

AGC tuner

Automatic frequency control (AFC) circuit with
sample-and-hold

Video preamplifier

Sound IF amplifier and demodulator

DC volume control or separate supply for starting the
horizontal oscillator

Audio preamplifier

Horizontal synchronization circuit with two control loops

Vertical synchronization (divider system) and sawtooth
generation with automatic amplitude adjustment for 50
and 60 Hz

Transmitter identification (mute)

GENERAL DESCRIPTION

The TDA8303/TDA8303A combines all small signal
functions (except the tuner) which are required for a
monochrome television receiver. For a complete black and
white receiver only the output stages for video, sound,
horizontal and vertical deflection and a tuner have to be
added.
The TDA8303 is for applications with npn tuners and the
TDA8303A for pnp tuners.

FUNCTIONAL DESCRIPTION

Video IF amplifier, demodulator and video amplifier

Each of the three AC-coupled IF stages permits the
omission of DC feedback and possesses a control range
in excess of 20 dB. An additional advantage is the
symmetry of the amplifier which results in a less critical
application.

The IF amplifier is followed by a passive synchronous
demodulator providing a regenerated carrier signal. This is
limited by a logarithmic limiter circuit prior to its application
to the demodulator. The limiter has a very low differential
phase shift which results in good differential gain and
phase figures.

The video amplifier also contains a white spot inverter and
a noise clamp which limits interference pulses to a point
below the peak sync level. This circuit is more effective
than a noise inverter and results in an improved picture
stability, with respect to interference.

AFC-circuit

The reference signal for the AFC circuit is obtained from
the demodulator tuned circuit. In this way only one tuned
circuit needs to be applied and only one adjustment has to
be carried out. The disadvantage with this method is that
the frequency spectrum of the signal fed to the detector is
determined by the SAW filter characteristic. This spectrum
is asymmetrical with respect to the picture carrier so that
the AFC output voltage is dependent on the video signal.

To overcome this video frequency dependency of the AFC
output, the demodulator output is followed by a
sample-and-hold circuit which samples during the sync
level of the signal. This means that only the carrier signal
is available to the AFC and it will not be affected by the
video information.

At very weak input signals the drive signal of the AFC
circuit will contain substantial noise. This noise has an
asymmetrical frequency spectrum causing an offset in the
AFC output voltage. This effect can be minimized by
applying a notch in the demodulator tuned circuit. The
sample-and-hold circuit is followed by an amplifier with
high output impedance, therefore the steepness of the of
the AFC control voltage is dependent on the load
impedance.

ORDERING INFORMATION

Note

1. SOT117-1; 1996 December 3.

EXTENDED TYPE

NUMBER

PACKAGE

PINS

PIN POSITION

MATERIAL

CODE

TDA8303

28

DIL

plastic

SOT117

(1)

TDA8303A

28

DIL

plastic

SOT117

(1)

Summary of Contents for TDA8303

Page 1: ...DATA SHEET Preliminary specification File under Integrated Circuits IC02 July 1992 INTEGRATED CIRCUITS TDA8303 TDA8303A Small signal combination IC for black white TV ...

Page 2: ...has a very low differential phase shift which results in good differential gain and phase figures The video amplifier also contains a white spot inverter and a noise clamp which limits interference pulses to a point below the peak sync level This circuit is more effective than a noise inverter and results in an improved picture stability with respect to interference AFC circuit The reference signa...

Page 3: ...e results in a larger value of the minimum sync pulse amplitude The slicing level is independent of the video information SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT Supply VP positive supply voltage pin 7 9 5 12 13 2 V IP supply current pin 7 90 125 160 mA Istart start current pin 11 note 1 6 5 9 mA Video V8 9 RMS IF sensitivity RMS value at 38 9 MHz note 2 20 40 65 µV G8 9 IF gain control range...

Page 4: ...July 1992 4 Philips Semiconductors Preliminary specification Small signal combination IC for black white TV TDA8303 TDA8303A Fig 1 Block diagram ...

Page 5: ...C When out of sync condition is detected by the coincidence detector the sound output is muted When no mute is required the minimum voltage level on pin 22 should be clamped to a high level of 5 V At this level the gating of the AGC is switched off and the phase 1 detector has a high output current for reliable catching of a new transmitter Vertical synchronization The TDA8303 TDA8303A embodies a ...

Page 6: ...s of the horizontal sync During weak signal and synchronized conditions the time constant is enlarged and the phase detector is gated This ensures a stable display which is not disturbed by the noise in the video signal When the circuit is not synchronized the time constant is fast and not gated to ensure a short catching time Combination of DC volume control and start up feature Pin 11 of the IC ...

Page 7: ...ntial input resistance note 3 1300 Ω C8 9 differential input capacitance note 3 5 pF G8 9 gain control range 74 dB V17 output signal expansion for 46 dB input signal variation note 4 1 dB V8 9 maximum input signal 100 170 mV Video Amplifier note 5 V17 zero signal output level note 6 5 4 V V17 peak sync level 2 3 2 5 2 7 V V17 video output signal amplitude note 7 2 3 2 65 3 0 V V17 white spot thres...

Page 8: ... 4 mA V5 output saturation voltage I5 2 mA 300 mV IL leakage current pin 5 1 µA VI input signal variation complete tuner control 0 2 2 4 dB V1 minimum voltage tuner take over 1 V AFC circuit I19 AFC sample and hold switch off current 0 1 mA IO output current pin 19 V19 0 V 0 1 0 3 mA ILO output leakage current pin 19 2 µA V18 AFC output voltage swing notes 18 and 19 10 5 11 5 V I18 available outpu...

Page 9: ... control 20 dB 0 5 dB S N signal to noise ratio note 16 47 dB V11 voltage with pin 11 disconnected 6 V I11 current with pin 11 short circuited to ground 1 mA V12 temperature dependence of the output signal amplitude Tamb 20 to 65 C 30 dB volume control and voltage of pin 11 fixed note 17 2 5 dB Volume control note 17 see Fig 8 R11 external control resistor note 17 4 7 kΩ OSS suppression of output ...

Page 10: ...TAL OUTPUT PIN 26 OPEN COLLECTOR V26 output limiting voltage 16 5 V VOL LOW level output voltage Isink 10 mA 0 2 0 5 V Isink maximum sink current 10 mA duty factor of output signal 46 tr rise time of output pulse 260 ns tf fall time of output pulse 100 ns HORIZONTAL FLYBACK INPUT PIN 27 I27 required input current during flyback pulse 0 01 1 0 mA COINCIDENCE DETECTOR V22 voltage for in sync conditi...

Page 11: ...re is valid for the complete video signal amplitude peak white to black see Fig 3 The non linearity is expressed as a percentage of the maximum deviation of a luminance step from the mean step with respect to the mean step 10 The test set up and input conditions are illustrated by Fig 4 The figures are measured at an input signal of 10 mV RMS 11 Measured with a source impedance of 75Ω 12 The sound...

Page 12: ...signals are measured with a SAW filter OFW 1956 connected in front of the IC input signal such that the input signal of the IC is 150 µV RMS 20 The minimum value is obtained by connecting a 1 8 kΩ resistor between pins 17 and 25 The slicing level can be varied by changing the value of this resistor higher resistor value results in larger value of the minimum sync pulse amplitude The slicing level ...

Page 13: ...all signal combination IC for black white TV TDA8303 TDA8303A Fig 2 Video output signal handbook full pagewidth MLA667 100 95 30 17 5 Fig 3 EBU test signal waveform line 330 handbook full pagewidth MBC211 100 86 72 58 44 30 64 60 56 52 48 44 40 36 32 22 12 10 26 µs ...

Page 14: ...ier PC Picture carrier All with respect to top sync level Value at 1 1 MHz 20 log VO at 4 4 MHz VO at 1 1 MHz 3 6 dB Value at 3 3 MHz 20 log VO at 4 4 MHz VO at 3 3 MHz handbook full pagewidth MLA666 ATTENUATOR SPECTRUM ANALYZER TEST CIRCUIT CC 34 5 MHz PC 38 9 MHz SC 33 4 MHz Σ gain setting adjusted for blue or yellow handbook full pagewidth MBC213 SC CC PC 30 dB 13 2 dB 3 2 dB SC CC PC 30 dB 13 ...

Page 15: ...lips Semiconductors Preliminary specification Small signal combination IC for black white TV TDA8303 TDA8303A Fig 5 Signal to noise ratio as a function of the input voltage 0 dB 100 mV Fig 6 Test set up AM suppression ...

Page 16: ...July 1992 16 Philips Semiconductors Preliminary specification Small signal combination IC for black white TV TDA8303 TDA8303A Fig 7 AM suppression Fig 8 Volume control characteristics ...

Page 17: ...July 1992 17 Philips Semiconductors Preliminary specification Small signal combination IC for black white TV TDA8303 TDA8303A Fig 9 Timing diagram ...

Page 18: ...ble 1 Switching levels coincidence detector CONDITION V22 CONTROL SENSITIVITY HORIZONTAL OSCILLATOR kHz µS T2 T1 T3 SCAN V22 6 7 V and strong signal 11 3 7 6 weak signal 1 3 1 3 1 V22 5 7 V and strong signal 11 3 7 6 weak signal 11 3 7 6 V22 0 7 11 3 7 6 Fig 10 Switching levels coincidence detector Fig 11 Anti top flutter pulse ...

Page 19: ...July 1992 19 Philips Semiconductors Preliminary specification Small signal combination IC for black white TV TDA8303 TDA8303A Fig 12 Application diagram ...

Page 20: ...1 17 95 01 14 A min A max b Z max ME e1 1 7 1 3 0 53 0 38 0 32 0 23 36 0 35 0 14 1 13 7 3 9 3 4 0 25 2 54 15 24 15 80 15 24 17 15 15 90 1 7 5 1 0 51 4 0 0 066 0 051 0 020 0 014 0 013 0 009 1 41 1 34 0 56 0 54 0 15 0 13 0 01 0 10 0 60 0 62 0 60 0 68 0 63 0 067 0 20 0 020 0 16 051G05 MO 015AH MH c e 1 ME A L seating plane A1 w M b1 e D A2 Z 28 1 15 14 b E pin 1 index 0 5 10 mm scale Note 1 Plastic o...

Page 21: ...he 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 DEFINITIONS LIFE SUPPORT APPLICATIONS These products are not designed for use in life support appliances devices or systems where malfunction of ...

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