View NTE789_70060.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

NTE789 Integrated Circuit Stereo Multiplex Decoder
Description: The NTE789, a monolithic silicon integrated circuit, is a stereo multiplex decoder intended for FM multiplex systems. This stereo multiplex decoder requires only one low-inductance tuning coil (requires only one adjustment for complete alignment), provides automatic stereo switching, energizes a stereo indicator lamp, and operates from a wide range of voltage supplies. Figure 1 shows the block diagram for the NTE789. The input signal form the detector is amplified by a low-distortion preamplifier and simultaneously applied to both signal, generated by a local voltage-controlled oscillator (VCO), is counted down by two frequency dividers to a 38kHz signal and to two 19-kHz pilot-tone supplied by the FM detector is compared to the locally generated 19-kHz signal in a synchronous detector. The resultant signal controls the voltage controlled oscillator (VC)) so that it produces an output signal to phase-lock the stereo decoder with the pilot tone. A second sychronous detector compares the locally generated 19-kHz signal with the 19-kHz pilot tone. If the pilot tone exceeds and externally adjustable threshold voltage, a Schmitt trigger circuit is energized. The signal from the Schmitt trigger lights the stereo indicator, enables the 38-kHz synchronous detector, and automatically switches the NTE789 form monaural to stereo operation. The output signal from the 38-kHz detector and the composite signal from the preamplifier are applied to a matrixing circuit from which emerge the resultant left and right channel audio signals. These signals are applied to their respective left and right post amplifiers for amplification to a level sufficient to drive most audio amplifiers. The NTE789 utilizes the 16-lead quad-in-line plastic package and operates over the ambient temperature range of -40C to +85C. Features: D Requires the use of only one low-inductance tuning coil D Automatic stereo switching D Directly drives a stereo indicator lamp up to 100mA D Includes driver for stereo-lamp indicator D Operates from a wide range of power supplies: 10 to 16 volts D Requires only one adjustment for alignment D Switching from monaural to stereo and stereo to monaural produces no audible thumps D Low distortion: under 0.5% D Separate dc input permits stereo defeat or enable D High signal output: directly drives audio amplifiers D Excellent SCA (storecast) rejection: 55dB typ. D High audio channel separation: 40dB typ.
Absolute Maximum Ratings: (TA = +25C unless otherwise specified) DC Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16V Current at Pin12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100mA Input Signal Voltage (Composite)(Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400mV Operating Ambient Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40 to +85C Storage Ambient Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -65 to +150C Lead Temperature (During Soldering, 1/32" (0.79mm) from case,10s max.) . . . . . . . . . . . . . . . . . . . . . +265C Note 1. For stereo operation, a minimum input signal voltage (composite) of 40mV is required. Electrical Characteristics: (TA = +25C, V+ = 12 unless otherwise specified) Parameter Static Characteristics
Total Current (Pin9, Pin10,Pin11) DC Voltage Pin1 Pin6 (Indicator Lamp OFF) Pin9 and Pin10 Pin12 (Indicator Lamp OFF) Voltage Differential (Pin2 - Pin1) Current at Pin12 (In actual use external circuit resistance (e.g. lamp should limit Pin12 to the maximum rated value of 100mA) Itotal V1 V6 V9, V10 V12 V2 - V1 VIN (at f = 19kHz) = 18mV V+ = 16V Lamp OFF - 1.6 - 3.7 12.7 - 75 22 2.3 2.1 5.4 - 0 100 27 3.1 3.6 7.4 - 0.1 - mA V V V V V mA
Symbol
Test Conditions
Min
Typ
Max
Unit
Static Characteristics
Input Impedance Channel Separatiom (L + R Reference) Channel Balance (Monaural) Monaural Gain Stereo/Monaural Gain Ratio Indicator Lamp - Turn-ON Voltage Capture Range (Deviation from 76kHz center frequency) Distortion (75s De-emphasis) 2nd Harmonic 3rd, 4th, and 5th Harmonic 19kHz Rejection 38kHz Rejection SCA (Storecast) Rejection Stereo Defeat Voltage (V4) Stereo Enable Voltage (V4) Zin VIN = 180mV, Note 3 VIN = 180mV VIN = 180mV VIN = 180mV, Note 3 19kHz pilot-tone at Pin1 19kHz pilot-tone voltage = 18mV - 25 - 3 - - 6.6 50k 40 0.3 6 0.3 4 10 - - 3.0 9 3.0 - - dB dB dB dB mV %
VIN = 240mV
- - - - - - > 1.6
0.2 < 0.1 35 25 55 - -
- - - - - < 0.9 -
% % dB dB dB V V
Note 2. For improved pilot sensitivity and overload characteristics, replace the .039F capacitor between Pin7 and Pin8 with a Series L-C Network (L = 4.7mH, C = 0.015F). Under these conditions, Indicator Lamp Sensitivity: "ON" = 3.3mV, "OFF" = 2.0mV. Note 3. For stereo operation, test conditions require a composite stereo input signal (modulated at 1kHz) including a 19kHz (18mV) pilot-tone signal.
Pin Connection Diagram
Composite FM 1 Detected Signal Input Bypass 2 GND 3 GND 4 GND 5 RC Network 6 19kHz Pilot Lamp 7 Sensitivity Network 8
Indicator Input 16 76kHz Network Capacitor Input 15 76kHz Network 14 Phase Lock Filter Loop Network 13 GND 12 Lamp Drive Circuit 11 (+) VCC 10 Right Ch Output 9 Left Ch Output
.012 (0.30) 16 .250 (6.35) 1 9 8 .400 (10.16) .200 (5.08)
.300 (7.62)
.099 (2.51) Min .785 (19.9) Max
.200 (5.08) Max
.020 (.508) .100 (2.54) .700 (17.78)

▲Up To Search▲

Price & Availability of NTE789

	To Download NTE789 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .