NTE NTE7018

NTE7018
Integrated Circuit
Small–Signal Subsystem for Color TV
Description:
The NTE7018 is a TV subsystem circuit intended to be used for base–band demodulation applications. This circuit consists of all small–signal functions (except the tuner) required for a quality color
television receiver. The only additional circuits needed to complete a receiver are a tuner, the deflection output stages, and a color decoder. The NTE1567 NTSC color decoder, and the NTE1754 vertical output, are ideal complements for the NTE7018.
Features:
D Vision IF amplifier with synchronous demodulation
D Tuner AGC (negative–going control voltage with increasing signal)
D AGC detector for negative modulation
D AFC circuit
D Video preamplifier
D Sound IF amplifier, demodulator, and preamplifier
D DC volume control
D Horizontal synchronization circuit with two control loops
D Extra time constant switches in the horizontal phase detector
D Vertical synchronization (divider system) and sawtooth generator with automatic amplitude
adjustment for 50 or 60HZ
D Three level sandcastle pulse
Applications:
D Color television receiver
D CATV converters
D Base–band processing
Absolute Maximum Ratings:
Supply Voltage (Pin7), VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.2V
Total Power Dissipation, PTOT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3W
Operating Ambient Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –25° to +65°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C
DC and AC Electrical Characteristics: (VCC = V7–6 = 12V, TA = +25°C, unless otherwise specified)
Parameter
Symbol
Min
Typ
Max
Unit
Supply Voltage (Pin7)
V7–6
9.5
12
13.2
V
Supply Current (Pin7)
I7
–
135
–
mA
V11–6
–
8.6
–
V
I11
–
6
8
mA
V8–9
60
–
100
120
140
–
µV
Differential Input Resistance (Pin8 and Pin9)
R8–9
800
1300
1800
Ω
Differential Input Capacitance (Pin8 and Pin9)
C8–9
–
5
–
pf
Gain Control Range
G8–9
56
60
–
dB
Maximum Input Signal
V8–9
50
100
–
mV
∆V17–6
–
1
–
dB
–
5.8
–
Supplies
Supply Voltage (Pin11, Note 1)
Supply Current (Pin11) for Horizontal Oscillator Start
Vision IF Amplifier (Pin8 and Pin9)
Input Sensitivity
(38.90MHZ on set AGC)
(45.75MHZ on set AGC)
Expansion of Output Signal for 50dB Variation of Input Signal
with V8–9 at 150µV (0dB)
Video Amplifier (measured at top sync input signal voltage (RMS value) of 10mV)
Output Level for Zero Signal Input
(Zero Point of Switched Demodulator)
V17–6
Output Signal Top Sync Level (Note 2)
V17–6
2.7
2.9
3.1
V
V17–6(P–P)
–
2.6
–
V
Internal Bias Current of Output Transistor
(NPN Emitter–Follower)
I17(INT)
1.4
2.0
–
mA
Bandwidth of Demodulated Output Signal
BW
5
–
–
MHZ
Differential Gain (Note 3)
G17
–
4
10
%
ϕ
–
3
10
deg.
Video Non–Linearity Complete Video Signal Amplitude (Note 4)
–
–
10
%
Intermodulation at Gain Control = 45dB
f = 1.1MHZ; blue
f = 1.1MHZ; yellow
f = 3.3MHZ; blue
f = 3.3MHZ; yellow
55
50
60
55
60
54
66
59
–
–
–
–
dB
50
50
54
56
–
–
Residual Carrier Signal
–
7
30
mV
2nd
–
24
30
mV
Amplitude of Video Output Signal (Peak–to–Peak Value)
Differential Phase (Note 3)
Signal–to–Noise Ratio (Note 5)
ZS = 75Ω, VI = 10mV
end of Gain Control Range
Residual
V
S/N
Harmonic of carrier Signal
dB
Tuner AGC (Note 13)
Minimum Starting Point Take–Over
V1–6(RMS)
–
–
0.5
mV
Maximum Starting Point take–Over
V1–6(RMS)
50
100
–
mV
I5MAX
6
8
–
mA
V5–6(SAT)
–
–
300
mV
I5
–
–
1
µA
∆VI
0.5
2.0
5.0
dB
V18–6(P–P)
9.5
10.35
11.0
V
±I18
–
2.6
–
mA
Maximum Output Swing
Output Saturation Voltage (I = 2mA)
Leakage Current
Input Signal Variation Complete Tuner Control (∆I5 = 2mA)
AFC Circuit (Pin18, Note 6)
AFC Output Voltage Swing
Available Output Current
DC and AC Electrical Characteristics (Cont’d): (VCC = V7–6 = 12V, TA = +25°C, unless otherwise
specified)
Parameter
Symbol
Min
Typ
Max
Unit
–
70
–
mV/
kHZ
V18–6
–
6
–
V
I18
–
TBD
–
µA
–
400
800
AFC Circuit (Cont’d) (Pin18, Note 6)
Control Steepness
Output Voltage at Nominal Tuning of the
Reference–Tuned Circuit
Offset Current AFC Output (Pin20 and Pin21 Short–Circuited)
Sound Circuit
µV
Input Limiting Voltage
(VO = VO MAX –3dB, QL = 16, fAF = 1kHZ, fC = 5.5MHZ)
V15LIM
Input Resistance (VI(RMS) = 1mV)
R15–6
–
2.6
–
kΩ
Input Capacitance (VI(RMS) = 1mV)
C15–6
–
6
–
pf
AM Rejection
AMR
–
–
46
50
–
–
dB
V12–6(RMS)
400
300
600
700
800
1200
mV
AF Output Impedance
Z12–6
–
25
100
Ω
Total Harmonic Distortion Volume Control 20dB,
(∆f = 27.5kHZ, Weighted Acc. CCIR 468)
THD
–
1
3
RR
–
–
35
30
–
–
dB
V12–6
–
3
–
V
S/N
–
45
–
dB
Voltage (Pin11 Disconnected)
V11–6
–
5
–
V
Circuit (Pin11 Short Circuited)
I11
–
0.9
–
mA
External Control Resistor
R11–6
–
5
–
kΩ
Suppression Output Signal During Mute Condition
OSS
–
66
–
dB
V25–6(P–P)
200
800
–
mV
I25
–
–
10
TBD
–
–
µA
mA
Holding Range PLL
±∆f
–
1100
1500
HZ
Catching Range PLL
±∆f
60
1000
–
HZ
–
–
–
2.5
3.75
7.5
–
–
–
∆tD/∆tO
–
50
–
tD
–
25
–
µs
–
25
–
µA/µs
–
±2
–
µs
(VI = 10mV)
(VI = 50mV)
AF Output Signal (∆f = 7.5kHZ, Minimum Distortion)
(∆f = 50kHZ, Pin11 used as Starting Pin)
Ripple Rejection
(fk = 100HZ, Volume Control 20dB)
(When Muted)
Output Voltage in Mute Condition
Signal–to–Noise Ratio (∆f = 27.5kHZ Weighted Noise, CCIR 468)
%
Volume Control
Sync Separator and First Control Loop
Required Sync Pulse Amplitude (R17–25 = 2kΩ, Note 7)
Input Current
(V25–6 > 5V)
(V25–6 = 0V)
Control Sensitivity (Note 8)
(Video to Oscillator, at Weak Signal)
(at Strong Signal During Scan)
(During Vertical Retrace and Catching)
kHZ/µs
Second Control Loop (Positive Edge)
Control Sensitivity (R28–6 = 47kΩ Trim Pot)
Control Range
Phase Adjustment (Via Second Control Loop)
Control Sensitivity
Maximum Allowed Phase Shift
a
DC and AC Electrical Characteristics (Cont’d): (VCC = V7–6 = 12V, TA = +25°C, unless otherwise
specified)
Parameter
Symbol
Min
Typ
Max
Unit
Free–Running Frequency (R = 34kΩ, C = 2.7nf)
fFR
–
15,625
–
HZ
Spread with Fixed External Components
∆f
–
0.4
4.0
%
∆fFR
–
0
0.5
%
TC
–
–
1 x 10–4
°C–1
Maximum Frequency Shift
∆fFR
–
–
10
%
Maximum Frequency Deviation at Start H–Out
∆fFR
–
8
10
%
Output Voltage (High Level)
(at which Protection Commences)
(Low, I26 = 10mA)
V26–6
–
–
–
–
–
0.15
13.2
15.8
0.5
V
Duty Cycle of Horizontal Output Signal (tp = 10µs)
d
–
0.45
–
Rise Time of Output Pulse
tR
–
260
–
ns
Fall Time of Output Pulse
tF
–
100
–
ns
Input Current Required During Flyback Pulse
I27
0.1
–
2.0
mA
Output Voltage (During Burst Key Pulse)
(During Horizontal Blanking)
(During Vertical Blanking)
V27–6
8.0
4.0
2.1
9.0
4.35
2.5
–
5.0
2.9
V
tW
3.1
3.6
3.5
4.0
3.9
4.4
µs
Horizontal Oscillator (Pin23)
Frequency Variation due to Change of Supply Voltage
from 9.5V to 13.2V
Frequency Variation with Temperature
Horizontal Output (Pin26)
Flyback Input and Sandcastle Output (Note 9)
Width of Burst Key Pulse (60HZ)
(50HZ)
Width of Horizontal Blanking Pulse
Flyback Pulse Width
Width of Vertical Blanking Pulse
(50HZ Divider in Search Window)
(60HZ Divider in Search Window)
(50HZ Divider in Narrow Window)
(60HZ Divider in Narrow Window)
–
–
–
–
21
17
25
21
–
–
–
–
–
5.2
–
µs
lines
Delay Between Start of Sync Pulse at Video Output and Rising
Edge of Burst Key Pulse
Coincidence Detector Mute Output (Note 10)
Voltage for In–Sync Condition
V22–6
–
10.3
–
V
Voltage for No–Sync Condition, No Signal
V22–6
–
1.5
–
V
Switching Level to Switch Off the AFC
V22–6
–
6.4
–
V
Hysteresis AFC Switch
V22–6
–
0.4
–
V
Switching Level to Activate Mute Function
(Transmitter Identification)
V22–6
–
2.4
–
V
Hysteresis Mute Function
V22–6
–
0.5
–
V
Charge Current in Sync Condition 4.7µs
I22(P–P)
0.7
1.0
–
mA
Discharge Current in Sync Condition 1.3µs
I22(P–P)
–
0.5
–
mA
Input Current During Scan
I2
–
0.5
2.0
µA
Discharge Current During Retrace
I2
–
0.4
–
mA
V2–6(p–P)
–
0.8
1.1
V
Vertical Ramp Generator (Note 11)
Sawtooth Amplitude
DC and AC Electrical Characteristics (Cont’d): (VCC = V7–6 = 12V, TA = +25°C, unless otherwise
specified)
Parameter
Symbol
Min
Typ
Max
Unit
I3
–
–
7
mA
V3–6
–
5.7
–
V
V4–6
V4–6(P–P)
–
–
3.3
1.2
–
–
V
I4
–
–
12
µA
∆tp
–
5
–
%
–
0
2
%
Vertical Output (Pin3)
Output Current
Maximum Output Voltage
Feedback Input (Pin4)
Input Voltage
(DC Component)
(AC Component (peak–to–peak value))
Input Current
Internal Precorrection to Sawtooth
Deviation Amplitude 50/60HZ
Vertical Guard (Note 12)
Active at a Deviation with Respect to the DC Feedback Level,
(V27–6 = 2.5V),
(at Switching Level Low)
(at Switching Level High)
∆V4–6
V
–
–
1.3
1.9
–
–
Note
1. Pin11 has a double function. When during switch–on a current of 6mA is supplied to this pin, this current is used
to start the horizontal oscillator. The main supply can then be obtained from the horizontal deflection stage.
When no current is supplied to this pin it can be used as volume control. The indicated maximum value is the
current at which all IC’s will start. Higher currents are allowed: the excess current is bypassed to GND.
Note
2. Signal with negative–going sync top white 10% of the top sync amplitude.
Note
3. The differential gain is expressed as a percentage of the difference in peak amplitudes between the largest and
smallest value relative to the subcarrier amplitude at blanking level. The differential phase is defined as the
difference in degrees between the largest and smallest phase angle.
Note
4. This figure is valid for the complete video signal amplitude (peak white to black).
VOUT BLACK–TO–WHITE
5. The S/N = 20 log
VN(RMS) at B = 5MHZ
6. The AFC control voltage is obtained by multiplying the IF–output signal (which is also used to drive the synchronous demodulator) with a reference carrier. This reference carrier is obtained from the demodulator tuned circuit via a 90° phase shift network. The IF–output signal has an asymmetrical frequency spectrum with respect
to the carrier frequency. To avoid problems due to this asymmetrical signal, the AFC circuit is gated by means
of an internally generated gating pulse. As a result the detector is operative only during black level at a constant
carrier amplitude which contains no additional side bands. As a result the AFC output voltage contains no video
information.
At very weak input signals, the driver signal for the AFC circuit will contain a lot of noise. This noise signal has
again an asymmetrical frequency spectrum and this will cause an offset of the AFC output voltage. To avoid
problems due to this effect, the AFC is switched off when the AGC is controlled to maximum gain.
The measured figures are obtained at an input sign RMS voltage of 10mV and the AFC output loaded with 2
times 220kΩ between +VS and GND. The unloaded Q–factor of the reference tuned circuit is 70. The AFC
is switched off when no signal is detected by the coincidence detector or when the voltage at Pin22 is between
1.2V and 6.4V. This can be realized by a resistor of 68kΩ connected between Pin22 and GND.
Note
Note
Note
7. The slicing level can be varied by changing the value of R17–25. A higher resistor value results in a larger value
of the minimum sync pulse amplitude. The slicing level is independent of the video information.
Note
8. Frequency control is obtained by supplying a correction current to the oscillator RC–network via a resistor, connected between the phase 1 detector output and the oscillator network. The oscillator can be adjusted to the
right frequency in one of the two following ways:
a) Interrupt R23–24.
b) Short circuit the sync separator bias network (Pin25) to +VCC.
To avoid the need of a VCR switch, the time constant of phase detector at strong input signal is sufficient short
to get a stable picture during VCR playback. During the vertical retrace period, the time constant is even shorter
so that the head errors of the VCR are compensated at the beginning of the scan. Only at weak signal conditions
(information derived from the AGC circuit) is the time constant increased to obtain a good noise immunity.
Note
9. The flyback input and sandcastle output have been combined on one pin. The flyback pulse is clamped to a
level of 4.5V. The minimum current to drive the second control loop is 0.1mA.
Note 10. The functions in–sync/out–of–sync and transmitter identification have been combined on this pin. The capacitor is charged during the sync pulse and discharged during the time difference between gating and sync pulse.
Note 11. The vertical scan is synchronized by means of a divider system. Therefore no adjustment is required for the
ramp generator. The divider detects whether the incoming signal has a vertical frequency of 50 or 60HZ and
corrects the vertical amplitude.
Note 12. To avoid screenburn due to a collapse of the vertical deflection, a continuous blanking level is inserted into the
sandcastle pulse when the feedback voltage of the vertical deflection is not within the specified limits.
Note 13. Starting point tuner takeover at 1 = 0.2mA. Takeover to be adjusted with a potentiometer of 47kΩ.
Pin Connection Diagram
AGC Take–over
1
28 Phase 2 Detector
Vertical Ramp Generator
2
Vertical Drive
3
27 Sandcastle Output/
Feedback Input
26 Horizontal Drive
Vertical Feedback
4
25 Sync Separator
Tuner AGC
5
24 Phase 1 Detector
GND
6
23 Horizontal Oscillator
VCC
7
22 Coincidence Detector Decouple
Vision IF Input
8
21 Sync Demodulator
Vision IF Input
9
20 Sync Demodulator
Decouple Capacitor 10
19 AGC Detector
Volume Control/ 11
Start Horizontal Oscillator
Audio Output 12
18 AFC Output
17 Video Output
Sound Demodulator 13
16 GND
Sound IF Decouple 14
15 Sound IF Input
14
1
15
28
1.469 (37.32)
Max
.540
(13.7)
.250
(6.35)
.100 (2.54)
1.300 (33.02)
.122
(3.1)
Min
.600
(15.24)