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, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.4V Supply Current, ICC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5mA Power Dissipation (TA = +75°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100mW Operating Ambient Temperature range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –20° to +75°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55° to +150°C Electrical Characteristics: (TA = +25°C, VCC = 3V unless otherwise specified) Parameter Input/Output Characteristics ENCODE Mode DECODE Mode Note 1. 0dB = 20mV = –34dBV Symbol Test Conditions Min Typ Max +10.0 +12.5 Unit VOE–1 VIN = +20dB, f = 1kHz +7.5 dB VOE–2 VIN = 0dB, f = 1kHz –2.0 0 +2.0 dB VOE–3 VIN = –40dB, f = 1kHz –23 –20 –17 dB VOD–1 VIN = +10dB, f = 1kHz +17 +20 +23 dB VOD–2 VIN = 0dB, f = 1kHz –2.0 0 +2.0 dB VOD–3 VIN = –20dB, f = 1kHz –44 –40 –36 dB Electrical Characteristics (Cont’d): (TA = +25°C, VCC = 3V unless otherwise specified) Parameter Symbol Maximum Output Voltage ENCODE Mode VOME Test Conditions THD = 1%, f = 1kHz Min Typ Max Unit 80 150 – mV 200 450 – mV DECODE Mode VOMD Total Harminic Distortion (DECODE Mode) THDD VO = +14dB, f = 1kHz – 0.15 0.3 % VNOE Input Short, A–weight – 100 200 µV – 3 6 µV – 0 1.2 dB – 0 1.2 Measuring Channel: Short Another Channel: Output 200mV, f = 1kHz 50 60 – dB f = 60Hz, V = 100mV, Input Short 40 55 – dB ICC VCC = 3V, Input Short – 1.8 3.2 mA VOFF VIN = +20dB, f = 1kHz 17 20 23 dB THDOFF VIN = +20dB, f = 1kHz – 0.3 1.0 % – 10 20 µV Noise Output Voltage ENCODE Mode DECODE Mode VNOD Difference Between Channels ENCODE Mode CDE DECODE Mode VIN = 0dB, f = 1kHz CDD Crosstalk (ENCODE Mode) CT Ripple Rejection Ratio (DECODE Mode) Quiescent Current Input/Output Characteristics dbx OFF Mode Total Harmonic Distortion dbx OFF Mode Output Noise Voltage (dbx OFF Mode) SVRR VnOFF Input Short, A–weight Note 1. 0dB = 20mV = –34dBV Pin Connection Diagram Adjust 1 GND 2 22 VCC 21 N.C. RMS Input A 3 20 RMS Input B Timing A 4 CCA Input A 5 19 Timing B 18 CCA Input B CAP1 A 6 17 CAP1 B CAP2 A 7 16 CAP2 B VOUT A 8 15 VOUT B ON/OFF A 9 NI 10 Decode 11 14 ON/OFF B 13 I Time 12 Encode 22 12 .410 (11.41) 1 11 .400 (10.16) 1.300 (33.0) .216 (5.5) .100 (2.54) 1.000 (25.4) .110 (2.79)