SSM2000 Analog, SSM2000 Datasheet
SSM2000
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SSM2000 Summary of contents
Page 1
... Cassette Tape Players AM/FM Receivers Telephone & Wireless Links Professional Audio GENERAL DESCRIPTION The SSM2000 is an advanced audio noise reduction system ® based on proprietary HUSH circuitry. HUSH combines a dy- namic filter and downward expander to provide a high level of effectiveness without the sonic artifacts normally associated with noise reduction systems ...
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... PASSBAND FREQUENCY 0 –10 –20 –30 –40 OUTPUT –50 LEVEL –60 –70 –80 –90 –100 Figure 3. Dynamic Filter Characteristic (For C Defeat Mode) –2– / kHz 100 dBu = 0.775 V rms. L SSM2000 Min Typ Max 0.02 0. 300 60 – ...
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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the SSM2000 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... The VCF has a user-definable cutoff range that is usually set from 1 kHz to 35 kHz. It can be set to cover other ranges as required by the application. The VCA can be adjusted from a loss to a gain, adding to the SSM2000’s versatility. In accordance with proprietary patented algorithms, control sig- JA3 ...
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... DEFEAT = ON (Pin 16) –8 MUTE = OFF (Pin 17 100k L –10 BOTH CHANNELS –12 20 100 1k FREQUENCY – Hz Figure 8. –3 dB Bandwidth REV. 0 Typical Performance Characteristics–SSM2000 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 1 2 rms Figure 9. Output vs. Input Characteristics (With Different Adaptive Threshold Voltage, Pin 17) – ...
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... SSM2000–Typical Performance Characteristics 10 0 – + 4.25V (Pin 5, 20) S – 300mV SINE WAVE (Pin 1, 2) rms IN –30 DEF THRESHOLD = 0V (Pin 14) DEFEAT = OFF (Pin 16) –40 MUTE = OFF (Pin 17 100k L –50 –60 –70 –80 –90 20 100 1k FREQUENCY – Hz Figure 11. Channel Output vs. Frequency for Different VCA Control Port Voltages – ...
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... APPLICATIONS INFORMATION Introduction The SSM2000 is a dual channel audio noise reduction IC which reduces noise through a combination of variable filtering and downward expansion in conjunction with a unique adaptive noise threshold detector. These two techniques yield an overall noise reduction and FM radio, open reel ...
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... VCA shuts down. For this reason, the maximum VCA at- tenuation in the SSM2000 is limited to 15 dB. In addition, the “smooth” roll-off of the downward expander eliminates any audible artifacts resulting from this type of noise reduction. In contrast, many noise reduction system employ gates and com- parators that result in dramatic shifts in attenuation ...
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... It is also unreasonable to expect the driver of an automobile to fiddle with panel controls in order to improve the threshold tracking. The patented adaptive noise threshold in the SSM2000 solves these problems, maintaining the transparency of the noise reduction system under most op- eration conditions while not introducing cumbersome end-user controls ...
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... SSM2000 Noise is most objectionable at high frequencies (3 kHz–8 kHz). Therefore, only the VCF detector output signal is used to deter- mine the adaptive noise threshold. Figures 25a–c, are a series of circuits which illustrate how the noise threshold is derived important to remember that the signal that is applied to the noise threshold detector circuitry has already been rectified and averaged ...
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... L IN and R IN are the inputs for the Left and Right channels. These are each single ended inputs with an input impedance The input driver for SSM2000 should be able to handle this load level without significant harmonic distortion. These inputs should be ac coupled with at least the minimum capaci- tor value shown in the example circuits, which is 6 ...
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... V+ (Pin the supply pin. Please refer to the sections “Powering the SSM2000—Dual Supply” and “Powering the SSM2000— Single Supply” for more information. ACOM (Pin 6) ACOM is the internal ground reference for the audio circuitry. ...
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... RC. The sig- nal is now representative of the long term average amplitude of the original audio that is applied to the L/R input of the SSM2000. This signal is then passed to the VCA control port. Audio Compression Audio compression can be thought of as fast automatic leveling. ...
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... OP292 3.3µF 20 –5V Figure 32. A Schematic to Use the SSM2000 in a Post- Volume Control Application PRECAUTIONS, LIMITATIONS, AND OBSERVATIONS Operating Temperature Under light loading conditions HUSH runs relatively cool, typi- cally only 4 C over ambient room temperature. If HUSH is hot, then check to make sure that the capacitive and resistive loading requirements are not being exceeded ...
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... RC 10k mon evaluation pitfalls. The SSM2000 has been designed as a stereo system result the input to the detector circuits is the sum of both the left and right inputs. Monaural signals that used during evaluation should be applied to both inputs, because the detectors’ input requires both the left and right signal ...
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... Rocktron Corp. reserves the right to approve use of the HUSH logo and may require submission of a schematic illustrating the use of the SSM2000; a physical sample of the end product may also be required. Applications for approval of the use of the HUSH name and logo may be obtained by contacting ADI. – ...