NTE1174
Integrated Circuit
TV Automatic Fine Tuning (AFT) Circuit
Description:
The NTE1174 is a monolithic TV Automatic Fine Tuning (AFT) circuit in a 14−Lead Staggered DIP
type package that provides an AFT voltage and an amplified 4.5MHz intercarrier sound signal. When
connected to an output of an IF amplifier the NTE1174 provides the signal processing (amplification
and detection) necessary to generate the AFT correction signals required by the TV tuner. It also
mixes the video and sound IF carriers and amplifiers the resultant 4.5MHz intercarrier sound signal.
The sound output may then be connected to an FM detector such as the NTE1175 “TV Sound IF and
Audio Output Subsystem,” or the NTE712 “FM Detector and Audio Driver.”
The AFT portion of the NTE1174 is similar the NTE 780 AFT circuit with the following exceptions:
(a) the AFT filter capacitors are external and user selectable, allowing the detector to operate as
a peak detector and resulting in a higher effective gain for the TV signal; (b) the detector bias resistor
is external and user selectable, allowing the gain of the AFT and intercarrier signals to be adjusted;
(c) the dynamic resistance of the shunt regulator has been decreased.
Absolute Maximum Ratings:
Device Dissipation (TA ≤ +55°C), PD630mW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Derate Linearly Above +55°C 6.67mW/°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Ambient Temperature Range, Topr −40° to +85°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage Temperatuere Range, Tstg −65° to +150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead Temperature (During Soldering, 1/16” from case, 10sec max), TL. +265°C. . . . . . . . . . . . . . . .
Electrical Characteristics: (TA = +25°C, V+ = 28V unless otherwise specified)
Parameter Test Conditions Min Typ Max Unit
No Signal Input
Supply Current, I+ 15 −20 mA
Low Voltage at Pin7 V+ = 20.8V, Note 1 11.0 −14.5 V
Shunt Regulator Voltage 12.0 −14.5 V
Quiescent Voltage at Pin3 4.5 −10 V
Quiescent Voltage at Pin13 and Pin14 Pin13 connected to Pin14, Note 2 6.0 −8.5 V
Quiescent Voltage at Pin6 1.4 −2.6 V
Note 1. I7 = 12mA maximum at V7 = 11V.
Note 2. V13 = 0.55 VZ ± 0.7V.
Electrical Characteristics (Cont’d): (TA = +25°C, V+ = 28V unless otherwise specified)
Parameter Test Conditions Min Typ Max Unit
Signal Input = 15mVRMS (Note 3, unless otherwise specified)
Correction Voltage at Pin13 f = 44.65MHz 2.2 −4.7 V
f = 45.69MHz 1.2 −4.4 V
f = 45.81MHz 9.6 −13.8 V
f = 46.85MHz 9.1 −12.1 V
Correction Voltage at Pin14 f = 44.65MHz 9.1 −12.1 V
f = 45.69MHz 9.6 −13.8 V
f = 45.81MHz 1.2 −4.4 V
f = 46.85MHz 2.2 −4.7 V
4.5MHz Output Two−Tone Input,
f1 = 45.75MHz at 15mV,
f2 = 41.25MHz at 5mV
50 −200 mVRMS
Note 3. Resistor from Pin6 to Pin7 = 9.09kΩ. Crossover sttepens and “bow−tie” width increases
when resistor is decreased in value. Total peak swing decreases slightly.
IF Amp Input
Filter A
Detector B Input
N.C. DC Amp B Output
Filter BSubstrate
Intercarrier Output
Detector A Input
DC Amp A Output
Zener
Detector Bias
IF Input
N.C.
1
2
3
4
5
6
7
14
13
12
11
10
9
8
Pin Connection Diagram
17
814
.260
(6.6)
Max
.770 (19.5) Max
.100
(2.54)
Max
.300 (7.62)
.200
(5.08)
.100 (2.54) .025
(0.64)
.200 (5.08)
Max
.600 (15.24) .400
(10.16)
