PHILIPS TDA3857

INTEGRATED CIRCUITS
DATA SHEET
TDA3857
Quasi-split sound processor with
two FM demodulators
Product specification
File under Integrated Circuits, IC02
June 1994
Philips Semiconductors
Product specification
Quasi-split sound processor with two
FM demodulators
TDA3857
FEATURES
• Quasi-split sound processor for all FM standards e. g. B/G
• Reducing of spurious video signals by tracking function and AFC for the vision carrier reference circuit; (recommended
for NICAM)
• Automatic muting of the AF2 signal by the input level
• Stereo matrix correction
• Layout-compatible with TDA3856 (24 pins) and TDA3858 (32 pins).
GENERAL DESCRIPTION
Symmetrical IF inputs. Gain controlled wideband IF amplifier.
AGC generation due to peak sync. Reference amplifier for the regeneration of the vision carrier. Optimized limiting
amplifier for AM suppression in the regenerated vision carrier signal and 90° phase shifter.
Intercarrier mixer for FM sound, output with low-pass filter.
Separate signal processing for 5.5 and 5.74 MHz intercarriers. Wide supply voltage range, only 300 mW power
dissipation at 5 V.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
MIN.
TYP.
MAX.
UNIT
VP
supply voltage (pin 19)
4.5
5
8.8
V
IP
supply current
−
60
72
mA
Vi IF
IF input sensitivity (−3 dB)
−
70
100
µV
Vo AF
audio output signal (RMS value)
−
1
−
V
THD
total harmonic distortion
−
0.5
−
%
S/N (W)
weighted signal-to-noise ratio
−
68
−
dB
ORDERING INFORMATION
PACKAGE
EXTENDED
TYPE NUMBER
PINS
PIN
POSITION
MATERIAL
CODE
TDA3857
20
DIL
plastic
SOT146(1)
Note
1.
SOT 146-1; 1996 November 28.
June 1994
2
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
Fig.1 Block diagram (standard B/G).
June 1994
3
TDA3857
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
TDA3857
PINNING
SYMBOL
PIN
DESCRIPTION
FMIF1
1
IF difference input 1 for B/G standard (38.9 MHz)
CAGC
2
charge capacitor for AGC
MATR
3
input for stereo matrix correction
FM2R1
4
reference circuit for FM2 (5.74 MHz)
FM2R2
5
reference circuit for FM2 (5.74 MHz)
AF2
6
AF2 output (AF out of 5.74 MHz)
AF1
7
AF1 output (AF out of 5.5 MHz)
FM1R1
8
reference circuit for FM1 (5.5 MHz)
FM1R2
9
reference circuit for FM1 (5.5 MHz)
VC-R1
10
reference circuit for the vision carrier (38.9 MHz)
VC-R2
11
reference circuit for the vision carrier (38.9 MHz)
TRACK
12
DC output level for tracking
FM1I
13
intercarrier input for FM1 (5.5 MHz)
CAF1
14
DC decoupling capacitor for FM1 demodulator
(AF1)
ICO
15
intercarrier output signal (5.5/5.74 MHz)
CAF2
16
DC decoupling capacitor for FM2 demodulator
(AF2)
FM2I
17
intercarrier input for FM2 (5.74 MHz)
GND
18
ground (0 V)
VP
19
+5 to +8 V supply voltage
FMIF2
20
IF difference input 2 for B/G standard (38.9 MHz)
June 1994
4
Fig.2 Pin configuration.
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
has to be adapted to other TV transmission standards if
necessary, according to the formula
FUNCTIONAL DESCRIPTION
The quasi-split sound processor is suitable for all FM
standards (e. g. B/G).
C s = C p ( f vc ⁄ f sc ) 2 – C p
The result is an improved intercarrier buzz (up to 10 dB
improvement in sound channel 2 with 250 kHz video
modulation for B/G stereo) or suppression of 350 kHz
video modulated beat frequency in the digitally-modulated
NICAM subcarrier.
B/G standard
AGC detector uses peak sync level. Sound carrier SC1
(5.5 MHz) provides AF1, sound carrier SC2 (5.74 MHz)
provides AF2.
Intercarrier buzz fine tuning with 250 kHz square
wave video modulation
Muting
With no sound carrier SC2 at pin 17, AF2 output is muted.
The mute circuit prevents false signal recognition in the
stereo decoder at high IF signal levels when no second
sound carrier exists (mono) and an AF signal is present in
the identification signal frequency range.
With 1 mV at pin 17, under measurement conditions, AF2
is switched on (see limiting amplifier). Weak input signals
at pins 1 and 20 generate noise at pin 17, which is present
in the intercarrier signal and passes through the 5.74 MHz
filter. Noise at pin 17 inhibits muting. No misinterpretation
due to white noise occurs in the stereo decoder, when
non-correlated noise masks the identification signal
frequencies, which may be present in sustained tone
signals. The stereo decoder remains switched to mono.
The picture carrier for quadrature demodulation in the
intercarrier mixer is not exactly 90 degrees due to the shift
variation in the integrated phase shift network. The tuning
of the LC reference circuit to provide optimal video
suppression at the intercarrier output is not the same as
that to provide optimal intercarrier buzz suppression. In
order to optimize the AF signal performance, a fine tuning
for the optimal S/N at the sound channel 2 (from 5.74 MHz)
may be performed with a 250 kHz square wave video
modulation.
Measurements at the demodulators
For all signal-to-noise measurements the generator must
meet the following specifications:
phase modulation errors < 0.5° for B/W-jumps intercarrier
signal-to-noise ratio as measured with ‘TV-demodulator
AMF2’ (weighted S/N) must be > 60 dB at 6 kHz sine
wave modulation of the B/W-signal.
Signal-to-noise ratios are measured with ∆f = ±50 kHz
deviation and fmod = 1 kHz; with a deviation of ±30 kHz the
S/N ratio is deteriorated by 4.5 dB.
Sound carrier notch filter for an improved intercarrier
buzz
The series capacitor Cs in the 38.9 MHz resonant circuit
provides a notch at the sound carrier frequency in order to
provide more attenuation for the sound carrier in the vision
carrier reference channel. The ratio of parallel/series
capacitor depends on the ratio of VC/SC frequency and
June 1994
TDA3857
5
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
TDA3857
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL
PARAMETER
MIN.
MAX.
UNIT
VP
supply voltage (pin 19)
−
8.8
V
VI
voltage (pins 1, 6, 7, 13, 15, 17 and 20)
0
VP
V
Ptot
total power dissipation
0
635
mW
Tstg
storage temperature
−25
+150
°C
Tamb
operating ambient temperature
0
+70
°C
VESD
electrostatic handling (note 1)
±500
−
V
all pins except pins 1 and 20
pins 1 and 20
+400
−
V
−500
−
V
Note to the Limiting Values
1. Equivalent to discharging a 200 pF capacitor through a 0 Ω series resistor.
CHARACTERISTICS
VP = 5 V and Tamb = +25 °C; measurements taken in Fig.3 with fVC = 38.9 MHz, fSC1 = 33.4 MHz and
fSC2 = 33.158 MHz. Vision carrier (VC) modulated with different video signals, modulation depth 100% (proportional to
10% residual carrier).
Vision carrier amplitude (RMS value) Vi VC = 10 mV; vision to sound carrier ratios are VC/SC1 = 13 dB and
VC/SC2 = 20 dB. Sound carriers (SC1, SC2) modulated with f = 1 kHz and deviation ∆f = 50 kHz, unless otherwise
specified.
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
VP
supply voltage (pin 19)
4.5
5
8.8
V
IP
supply current (pin 19)
48
60
72
mA
IF amplifier (pins 1 and 20)
RI
input resistance
1.8
2.2
−
kΩ
CI
input capacitance
−
2.0
2.6
pF
VI
DC input voltage
−
1.75
−
V
Vi IF (RMS)
maximum input signal (RMS value,
pins 1-20)
Vo = +1 dB
70
100
−
mV
input signal sensitivity (RMS value)
−3 dB intercarrier signal
reduction at pin 15
−
70
100
µV
∆Gv
IF gain control
60
63
−
dB
V2
voltage for gain control (pin 2)
1.7
−
2.6
V
B
IF bandwidth
−3 dB
50
70
−
MHz
fo = 38.9 MHz
−
270
−
mV
−
4
−
kΩ
−
0.247
−
µH
−
68
−
pF
Resonance amplifier (pins 10-11)
Vo (p-p)
vision carrier amplitude
(peak-to-peak value)
R10-11
operating resistance
L
inductance
C
capacitance
June 1994
Figs 3 and 4
6
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
SYMBOL
PARAMETER
CONDITIONS
MIN.
TDA3857
TYP.
MAX.
UNIT
−
40
−
VP − 1 −
V
output signal for 5.5 MHz (RMS value)
71
95
125
mV
output signal for 5.74 MHz (RMS
value)
32
43
56
mV
−1 dB
6
8.5
−
MHz
−3 dB
7
10
−
MHz
QL
Q-factor of resonance circuit
V10, 11
DC voltage (pins 10 and 11)
Qo = 90
−
Intercarrier mixer output (pin 15)
Vo (RMS)
B
IF bandwidth
VVID/V15
residual video AM on intercarrier
note 1
−
3
10
%
VVC (RMS)
residual vision carrier (RMS value)
1st/2nd harmonic
(38.9/77.8 MHz)
−
0.5
1
mV
R15
output resistance (emitter follower)
1 mA emitter current
−
30
−
Ω
Io
allowable AC output current (pin 15)
−
−
±0.7
mA
I15
allowable DC output current
−
−
−2
mA
V15
DC voltage
LC-circuit at pin 10, 11
adjusted to minimum
video content at pin 15
1.5
1.75
2.0
V
−3 dB AF signal
−
300
450
µV
200
−
−
mV
Limiting amplifiers (pins 13 and 17)
Vi (RMS)
minimum input signal (RMS value)
maximum input signal (RMS value)
R13, 17
input resistance
450
560
700
Ω
V13, 17
DC voltage
−
0
−
V
Vi (RMS)
level detector threshold for no muting
(RMS value, pin 17)
0.8
1.2
1.7
mV
∆Vi
hysteresis of level detector
4
7
12
dB
only 5.74 MHz channel
FM1 and FM2 demodulators
Measurements with FM IF input signals of 5.5 MHz and 5.74 MHz with Vi IF (RMS) = 10 mV (fmod = 1 kHz, deviation
∆f = ±50 kHz) at pins 13 and 17 without ceramic filters, Rs = 50 Ω.
De-emphasis 50 µs.
QL-factor = 11 for resonant circuits at pins 4-5 and 8-9 (including IC).
VIC (RMS)
intercarrier signals
(RMS values, pins 4-5 and 8-9)
−
100
−
mV
V
DC voltage (pins 4, 5, 8 and 9)
−
1.8
−
V
Vo (RMS)
AF output signals
(RMS values, pins 6 and 7)
0.84
0.95
1.07
V
∆Vo
difference of AF signals between
channels (pins 6 and 7)
−
−
1
dB
R6, 7
output resistance
75
100
130
Ω
V6, 7
DC voltage
1.8
2.1
2.4
V
June 1994
note 2
7
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
SYMBOL
I6, 7 (M)
PARAMETER
allowed AC current of emitter output
(peak value)
CONDITIONS
note 3
MIN.
−
TDA3857
TYP.
−
MAX.
UNIT
±1.5
mA
I6, 7
maximum allowed DC output current
−
−
−2
mA
THD
total harmonic distortion
−
0.5
1.0
%
Vo (RMS)
AF output signal (RMS value)
1.25
−
−
V
THD = 1.5%
αAM
AM suppression
1 kHz; m = 0.3
48
54
−
dB
S/N(W)
weighted signal-to-noise ratio
CCIR468-3
64
68
−
dB
B
AF bandwidth (−3 dB)
lower limit
−
−
20
Hz
upper limit
100
−
−
kHz
60
70
−
dB
minimum output signal
−
0
−
V
maximum output signal
−
5
−
V
−1.5
−2.5
−
dB
αCR
crosstalk attenuation (pins 6-7)
V3
adjustment voltage for AF2
note 4
∆GAF2min
gain for minimum Vout
V3 = 0 V
∆GAF2max
gain for maximum Vout
V3 = 5 V
V14, 16
DC voltage (pins 14 and 16)
1.0
1.5
−
dB
−
1.8
−
V
Tracking Automatic Frequency Control (AFC) of the vision carrier reference circuit
VP − 3.3 −
VP − 1 V
black picture
−
9
−
white test picture
−
4
−
50% grey picture
−
6
−
black picture
−
−8
−
mV/kHz
white test picture
−
−3
−
mV/kHz
50% grey picture
−
−5.5
−
mV/kHz
70
−
−
dB
−
5
25
mV
Vo 12
tracking output voltage (pin 12)
FTR
tracking reducing factor for
S
note 5
AFC steepness (open loop) for
AF signal switches
input signals: FM intercarrier into pin 13
see part FM demodulator
no signal in pin 17 (AF2)
the output signals are related to the signals described in the demodulator part.
Vo/Vomute
AF2 mute attenuation (pin 6)
dV6
DC jump at the AF2 output
June 1994
switching to Mute
8
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
SYMBOL
PARAMETER
CONDITIONS
MIN.
TDA3857
TYP.
MAX.
UNIT
AF performance for FM operation (standard B/G)
input signals: B/G IF input signal (pin 1, 20)
unmodulated sound carriers
different video modulation (100%)
the output signals are related to the signals described in the demodulator part.
(S+N)/N(W) weighted signal-to-noise ratio
CCIR468-3;
de-emphasis 50 µs
black picture
fi = 5.5 MHz
59
63
−
dB
2T/20T pulses with white bar
fi = 5.5 MHz
57
61
−
dB
6 kHz sine wave, B/W-modulated
fi = 5.5 MHz
52
56
−
dB
250 kHz square wave, B/W-modulated fi = 5.5 MHz
50
54
−
dB
black picture
fi = 5.742 MHz
57
61
−
dB
2T/20T pulses with white bar
fi = 5.742 MHz
55
59
−
dB
6 kHz sine wave, B/W-modulated
fi = 5.742 MHz
50
54
−
dB
250 kHz square wave, B/W-modulated fi = 5.742 MHz
48
52
−
dB
30
40
−
dB
Ripple rejection of the AF outputs
RR
ripple rejection
Vripple on VP / Vripple on Vout
VR(p-p) = 200 mV;
fR = 70 Hz
Notes to the characteristics
1. Spurious intercarrier AM: M = (A − B)/A
(A = signal at sync; B = signal with 100% picture modulation).
2. AF signal can be adjusted by V3.
3. For larger current: RL > 2.2 kΩ (pin 6 or 7 to GND) in order to increase the bias current of the output emitter follower.
4. If not used, pin 3 should not be connected.
5. Automatic Frequency Control (AFC) of the vision carrier reference circuit (pins 10 and 11) for reducing spurious video
signals in the stereo/dual sound modes. The factor of reducing FTR at deviation ∆fVC specifies the ratio of spurious
signals with/without tracking function.
June 1994
9
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
TDA3857
(1) CP = 47 pF with optional use of tracking
(because of Co of the varicaps).
Fig.3 Test and application circuit for standard B/G (for application SAW-filters must be used).
(1) simple resonant circuit
(2) resonant circuit with CP = 68 pF
CS = CP (fVC/fSC)2 − CP
CS = 27 pF (see Fig.3)
Fig.4 Frequency response of the 38.9 MHz reference circuit.
June 1994
10
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
APPLICATION INFORMATION
Fig.5 Internal circuits (continued in Fig.6).
June 1994
11
TDA3857
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
Fig.6 Internal circuits (continued from Fig.5).
June 1994
12
TDA3857
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
TDA3857
PACKAGE OUTLINE
DIP20: plastic dual in-line package; 20 leads (300 mil)
SOT146-1
ME
seating plane
D
A2
A
A1
L
c
e
Z
b1
w M
(e 1)
b
MH
11
20
pin 1 index
E
1
10
0
5
10 mm
scale
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
UNIT
A
max.
A1
min.
A2
max.
b
b1
c
mm
4.2
0.51
3.2
1.73
1.30
0.53
0.38
0.36
0.23
26.92
26.54
inches
0.17
0.020
0.13
0.068
0.051
0.021
0.015
0.014
0.009
1.060
1.045
D
e
e1
L
ME
MH
w
Z (1)
max.
6.40
6.22
2.54
7.62
3.60
3.05
8.25
7.80
10.0
8.3
0.254
2.0
0.25
0.24
0.10
0.30
0.14
0.12
0.32
0.31
0.39
0.33
0.01
0.078
(1)
E
(1)
Note
1. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
SOT146-1
June 1994
REFERENCES
IEC
JEDEC
EIAJ
SC603
13
EUROPEAN
PROJECTION
ISSUE DATE
92-11-17
95-05-24
Philips Semiconductors
Product specification
Quasi-split sound processor with two FM demodulators
TDA3857
with the joint for more than 5 seconds. The total contact
time of successive solder waves must not exceed
5 seconds.
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.
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 (Tstg 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.
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).
Repairing 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.
Soldering by dipping or by wave
The maximum permissible temperature of the solder is
260 °C; solder at this temperature must not be in contact
DEFINITIONS
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.
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.
June 1994
14