as2521t austriamicrosystems, as2521t Datasheet
as2521t
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as2521t Summary of contents
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Preliminary Austria Mikro Systeme International AG Key Features Line/speech circuit, loudhearing, handsfree and dc/dc converter on one 28 pin CMOS chip Operating range from 13 to 100 mA (down with reduced performance) Soft clipping control eliminating harsh ...
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Preliminary Pin Description Pin # Name Type Supply Supply GND 6 STB AI 7 LLC DI 8 LSI RTH AI ...
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Preliminary VOL D/ Supply AI DI: Digital Input DO: Digital Output DI/O: Digital Input/Output Operating ...
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Preliminary Functional Description The AS252x contains all the voice circuits needed in a high feature telephone instrument, i .e.: line adaptation (ac impedance, dc characteristics, 2/4-wire conversion, power extraction) handset speech circuit loudhearing with enhanced anti-Larsen handsfree with dynamic loop ...
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Preliminary DC Conditions The normal operating range (off-hook) is from 100 mA. Operating range performance is from (parallel operation). In the normal operating range all functions are operational. In the line hold ...
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Preliminary The acoustic stability is provided as follows: When the volume is increased, e. dB, the receive gain maintains the same as long as no receive signal is applied. Applying a receive signal will cause ...
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Preliminary This approach has some disadvantages. It requires a high degree of discipline, since the three state channel control gives a very distinct half duplex with a relative high switching time constant to avoid chopper effects. Furthermore, the system is ...
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Preliminary The speech compression allows a higher gain in the transmit channel, i.e. the microphone gets more sensitive at low sound pressure levels on the microphone, which enables the user to move further away from the telephone. This means that ...
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Preliminary Electrical Characteristics Absolute Maximum Ratings* Supply Voltage............................................................................................................................... -0.3 Input Current..........................................................................................................................................+/- 25 mA Input Voltage (LS) ....................................................................................................................... -0.3V Input Voltage (LI, CS, SS).............................................................................................................-0.3V Input Voltage (STB, RI).........................................................................................................-2V Digital Input Voltage .......................................................................................................... -0.3V Electrostatic Discharge ..........................................................................................................................+/- 1000V Storage Temperature Range........................................................................................................... -65 ...
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Preliminary AC Electrical Characteristics mA 800 Hz; recommended operating conditions unless otherwise specified. LINE Transmit Symbol Parameter A Gain (M1/M2 to LS) TX Gain (M3/M4 to LS) A Gain ( Variation ...
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Preliminary Receive Symbol Parameter A Gain (LS to RO), Default RX LSP Gain (LSI to LO) Variation with Frequency A TX/F A Gain Range, LLC LLC A Volume Range RX THD Distortion V Soft Clip Level (RO) SC Soft Clip ...
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Preliminary Test Circuit Rev. 5.1 AS252x Figure 8: Test Circuit Page 12 AS2520/21/20B/21B May 1999 ...
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Preliminary Application Diagramme INPUT FOR DTMF AND TONE RINGER MELODIES CONTROL INPUTS (FROM µC) 1µ5 1µ5 510 510 33 n 5k6 MPSA92 2.2 mH 5V1 Applications Hints Interface to Microcontroller In off-hook condition the microcontroller can be ...
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Preliminary Pin Configuration 28 Pin SOP/DIP GND STB 6 23 VOL LLC LSI 8 21 ...