NTE NTE787

NTE787
Integrated Circuit
AM Receiver Subsystem
For Applications in a variety of AM broadcast and communications receivers and applications
requiring an array of amplifiers.
Description:
The NTE787, a monolithic integrated circuit, is an AM subsystem that provides the converter, IF amplifier, detector, and audio preamplifier stages for an AM receiver. It also provides internal AGC for the
first IF amplifier stage, delayed AGC for an optional external RF amplifier, a buffer stage to drive a
tuning meter, and terminals facilitating the optional use of a tone control.
This device features four independent transistor amplifiers, each incorporating internal biasing for
temperature tracking. These amplifiers are particularly useful in general–purpose amplifier, oscillator,
and detector applications in a wide variety of equipment designs.
The NTE787 utilizes a 16–Lead DIP package and operates over an ambient temperature range of
–40° to +85°C.
Features:
D Excellent overload characteristics
D AGC for IF amplifier
D Buffered output signal for tuning meter
D Internal Zener diode provides voltage regulation
D Two IF amplifiers stages
D Low–noise converter and first IF amplifier
D Low harmonic distortion (THD)
D Delayed AGC for RF amplifier
D Terminals for optional inclusion of tone control
D Operates from wide range of power supplies: V+ = 6 to 16 volts
D Optional AC and/or DC feedback on wide–band amplifier
D Array of amplifiers for general–purpose applications
D Suitable for use with optional external RF stage, either MOS or bipolar
Absolute Maximum Ratings: (TA = +25°C unless otherwise specified)
DC Supply Voltage (Across Pin5 and Pin3, Pin6, Pin13, Pin16 respectively) . . . . . . . . . . . . . . . 16V
DC Current
At Pin3, Pin6, Pin13, Pin16 respectively . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10mA
At Pin10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30mA
Device Dissipation (Up to TA = +50°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 760mW
Derate Above TA = +50°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.6mW/°C
Operating Ambient Temperature Range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40° to +85°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C
Lead Temperature (During Soldering, 1/32” from case, 10sec max), TL . . . . . . . . . . . . . . . . . +265°C
Electrical Characteristics: (TA = +25°C, V+ = 12V unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
V1, V4, V9, V11
–
0.7
–
V
V2, V7, V8
–
1.4
–
V
Pin10
V10
–
5.6
–
V
Pin12
V12
–
0
–
V
Pin15
V15
–
3.5
–
V
DC Current
Pin3
I3
–
0.35
–
mA
Pin6
I6
–
1.0
–
mA
Pin10
I10
–
20
–
mA
Pin13
I13
–
0
–
mA
Pin16
I16
–
1.2
–
mA
30% Modulation
–
75
–
mVrms
f = 1kHz
–
30
–
dB
VOUT = 100mV
–
0.2
–
%
fIN = 1MHz,
Signal–to–Noise Ratio (S/N) = 20dB
–
200
–
µV/m
–
100
–
µV/m
Static Characteristics
DC Voltage
Pin1, Pin4, Pin9, Pin11
Pin2, Pin7, Pin8
Dynamic Characteristics
Detector Output
Audio Amplifier Gain
AAF
Audio Distortion
Sensitivity
At Converter Stage Input
At RF Stage Input
Total Harmonic Distortion
THD
30% Modulation
–
1.0
–
%
Input Resistance
At Transistor Q1
RIN
No AGC,
Input Frequency Signal (fIN) = 1MHz
–
3500
–
Ω
–
2000
–
Ω
–
17
–
pF
–
12
–
pF
–
1.5
–
pF
–
1.5
–
pF
At Transistor Q5
Input Capacitance
At Transistor Q1
CIN
At Transistor Q5
Feedback Capacitance
At Transistor Q1
At Transistor Q5
CFB
Pin Connection Diagram
Converter Input Bypass
1
16 VCC
Converter Input
2
15 Audio Output
Converter Output
3
14 From Detector Filter
1st IF Amp Input
4
13 AGC Output from RF Amp
Substrate GND
5
12 To Tuning Meter
1st IF Amp Output
6
11 AGC Filter
2nd IF Feedback
7
10 VCC
2nd IF Amp Input
8
9
16
9
1
8
To Detector Filter & Audio
.260
(6.6)
Max
.870 (22.0)
Max
.200 (5.08)
Max
.100 (2.54)
.700 (17.78)
.099 (2.5) Min