NTE NTE1744 Datasheet

NTE1744

Integrated Circuit

Dual dbxII Noise Reduction System

Description:

The NTE1744 is an integrated circuit in a 22–Lead DIP type package designed for use in dbxII noise
reduction circuits for stereo applications. This device can be used for U.S. sound multiplex TV ap­plications and low voltage operation (1.8V) allows the NTE1744 to be used in battery–operated Hi–Fi
equipment.

Features:

D Wide Dynamic Range: 110dB
D Low Operating Voltage: VCCmin = 1.8V
D Minimum Number of External Components
D Adjustment: Only One
D Low Power Consumption
D Wide Operating Voltage Range: VCC = 1.8V to 14V

Absolute Maximum Ratings: (TA = +25°C unless otherwise specified)
Supply Voltage, V

Supply Current, I
Power Dissipation (TA = +75°C), P

CC

CC

D

Operating Ambient Temperature range, T
Storage Temperature Range, T

stg

opr

–20° to +75°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

–55° to +150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14.4V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

100mW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Characteristics: (TA = +25°C, VCC = 3V unless otherwise specified)

Parameter Symbol Test Conditions Min Typ Max Unit

Input/Output Characteristics

ENCODE Mode V

DECODE Mode V

V
V

V
V

OE–1
OE–2
OE–3
OD–1
OD–2
OD–3

VIN = +20dB, f = 1kHz +7.5 +10.0 +12.5 dB
VIN = 0dB, f = 1kHz –2.0 0 +2.0 dB
VIN = –40dB, f = 1kHz –23 –20 –17 dB
VIN = +10dB, f = 1kHz +17 +20 +23 dB
VIN = 0dB, f = 1kHz –2.0 0 +2.0 dB
VIN = –20dB, f = 1kHz –44 –40 –36 dB

Note 1. 0dB = 20mV = –34dBV

Electrical Characteristics (Cont’d): (TA = +25°C, VCC = 3V unless otherwise specified)

Parameter Symbol Test Conditions Min Typ Max Unit

Maximum Output Voltage

ENCODE Mode V

DECODE Mode V

Total Harminic Distortion

(DECODE Mode)

Noise Output Voltage

ENCODE Mode V

DECODE Mode V

Difference Between Channels

ENCODE Mode CD

DECODE Mode CD

Crosstalk (ENCODE Mode) CT Measuring Channel: Short

Ripple Rejection Ratio (DECODE Mode) SVRR f = 60Hz, V = 100mV, Input Short 40 55 – dB

OME

OMD

THDDVO = +14dB, f = 1kHz – 0.15 0.3 %

NOE

NOD

THD = 1%, f = 1kHz 80 150 – mV

200 450 – mV

Input Short, A–weight – 100 200 µV

– 3 6 µV

VIN = 0dB, f = 1kHz – 0 1.2 dB

E
D

Another Channel: Output 200mV, f = 1kHz

– 0 1.2

50 60 – dB

Quiescent Current I
Input/Output Characteristics

dbx OFF Mode

Total Harmonic Distortion

dbx OFF Mode

Output Noise Voltage (dbx OFF Mode) Vn

Note 1. 0dB = 20mV = –34dBV

Adjust

RMS Input A

Timing A

CCA Input A

CAP1 A

VCC = 3V, Input Short – 1.8 3.2 mA

CC

V

THD

OFF

VIN = +20dB, f = 1kHz 17 20 23 dB

OFFVIN

OFF

Pin Connection Diagram

= +20dB, f = 1kHz – 0.3 1.0 %

Input Short, A–weight – 10 20 µV

1

GND

2
3
4
5
6

V

22

CC

21

N.C.
RMS Input B

20
19

Timing B

18

CCA Input B
CAP1 B

17

CAP2 A

V

AV

OUT

ON/OFF A

NI

Decode

7
8

16
15

10 13
11 12

CAP2 B

B

OUT

ON/OFF B9 14
I Time

Encode