NTE NTE2004

NTE2004
Integrated Circuit
[
Dolby Noise Reduction Circuit
Description:
The NTE2004 is a monolithic audio noise reduction circuit in a 16–Lead DIP type package designed
for use in Dolby B–Type noise reduction systems. This device is used to reduce the level of background noise introduced during recording and playback of audio signals on magnetic tape and to improve the noise level in FM broadcast reception.
Features:
D Accurate Record Mode Frequency Response
D Excellent Frequency Response Tracking with Temperature and VCC ±0.4dB Typ
D Excellent Back–to–Back Dynamic Response – DC Shift Less Than 20mV Typ
D Improved Stability of all OP Amps
D High Reliability Packaging
Absolute Maximum Ratings:
Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24V
Operating Temperature Range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C
Lead Temperature (During Soldering, 60sec max), TL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +300°C
Electrical Characteristics: (TA = +25°C, VCC = 12V, f = 20Hz to 20kHz. All levels referenced to
580mVrms(0dB) unless otherwised specified)
Parameter
Test Conditions
Supply Voltage Range
Min
Typ
Max Unit
8
–
20
V
–
16
24
mA
Supply Current
VCC = 12V
Voltage Gain
(Pin5–3)
f = 1kHz, Pin6 and Pin2 Connected
24.5
26.0
27.5
f = 1kHz, 0dB at Pin3, Noise Reduction Out
–0.5
0
+0.5
dB
f = 20Hz to 10kHz, 0dB
–
0.05
0.2
%
f = 20Hz to 10kHz, +10dB
–
0.2
0.5
%
(Pin3–7)
Total Harmonic Distortion
2nd Harmonic
3rd Harmonic
dB
Signal Handling
VCC = 12V, 1% Distortion at 1kHz
+12
+15
–
dB
Signal–to–Noise Ratio
Record Mode
Note 1
64
72
–
dB
74
82
–
dB
Playback Mode
Note 1. All noise levels are measured CCIR/ARM weighted using a 10K source with respect to
Dolby level.
Electrical Characteristics (Cont’d): (TA = +25°C, VCC = 12V, f = 20Hz to 20kHz. All levels
referenced to 580mVrms(0dB) unless otherwised specified)
Parameter
Test Conditions
Record Mode Frequency Response
(At Pin7) Referenced to Encode
Monitor Point (Pin3)
Min
Typ
Max
Unit
–1.5
0
+1.5
dB
–20dB
–17.1 –15.6 –14.1
dB
–30dB
–24.0 –22.5 –21.0
dB
0dB
–1.2
+1.8
dB
–20dB
–18.3 –16.8 –15.3
dB
–30dB
–23.3 –21.8 –20.3
dB
–40dB
–30.2 –29.7 –28.2
dB
–1.5
0
+1.5
dB
f = 1.4kHz 0dB
f = 5kHz
+0.3
Back–to–Back Frequency Response
Using Typical Record Mode Frequency
Response Test Points
Input Resistance
Pin5
35
50
65
kΩ
Pin2
3.1
4.2
5.3
kΩ
Pin6
1.9
2.4
3.1
kΩ
Pin3
–
80
120
kΩ
Pin7
–
80
120
kΩ
–
±0.4
–
dB
–
±0.4
–
dB
Output Resistance
Back–to–Back Frequency Response Shift
Versus Temperature
0° to +70°C
Versus Supply Voltage
8V to 20V
16
9
1
8
Pin Connection Diagram
C Input
1
16 VCC
B Input
2
15 F Control
B Output
3
14 G Output
Reference 4
13
.260 (6.6)
Max
.870 (22.0) Max
A Input
5
12 D Input
A Output
6
11 C Output
S Output
7
10 D Filter
8
9
.200 (5.08)
Max
GND
.100 (2.54)
.700 (17.78)
.099 (2.5) Min