PBL38570 Ericsson Microelectronics, PBL38570 Datasheet
PBL38570
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PBL38570 Summary of contents
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Description. PBL 38570 is a monolithic integrated speech transmission circuit for use in electronic telephones designed to accomodate either a low impedance dynamic or an electret microphone. A separate input for DTMF dialling tones that is controlled by ...
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PBL 385 70 Maximum Ratings Parameter Line voltage Line current, continuous DIP Line current, continuous SO package Operating temperature range Storage temperature range No input should be set on higher level than pin 4 (+C). ...
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Electrical Characteristics cable and line rectifier unless otherwise specified. Amb Ref. Parameter Line voltage Transmitting gain, note 1 Transmitting range of regulation Transmitting frequency response Transmitter input impedance pin 3 Transmitter ...
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PBL 385 Mute DCS 7 DCO 8 DCC 9 Figure 5. Pin configuration. Pin Descriptions Refer to figure 5. DIP SO Name Function Output of ...
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Functional description Design procedure ; ref. to fig.4. The design is made easier through that all settable parameters are returned to ground (-line) this feature differs it from bridge type solutions. To set the parameters in the following order will ...
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... V 1 telephoneline line Microphone amplifier The microphone amplifier in PBL38570 is divided into two stages. The first stage is a true differential amplifier providing high CMRR (-55 to -65 dB typical) with voltage gain of 19 dB. This stage is followed by a gain regulated amplifier with a regulation range ...
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... Figure 10. Network and frequency plots between microphone amplifier and transmitter. Transmitter amplifier The transmitter amplifier in PBL38570 consists of three stages. The first stage is an amplitude limiter for the input signal at TI, in order to prevent the transmitted sig- nal to exceed a certain set level and cause distortion ...
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PBL 385 70 amplitude that can be transmitted to the line undistorted is dependent of R6. (amplitude limiting). The transmitter gain and frequency re- sponse are set by the RC-network between the pins 11 and 3. See fig.10. The capacitor ...
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What is balancing the side tone ? • To understand that side tone balancing is to counteract the signal, that is transmitted via the microphone and transmitter to the line, returning to the earphone via the receiver. • That presence ...
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PBL 385 70 a) PBL Mute Mute 385 70 I Mute Mute -L Figure 15. Mute principles. Mute function The circuit has a mute function at pin 5. Sinking current from this pin will cut off the ...
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The circuit has further two temperature and line current compensated DC supplies DC1 and DC2. DC1 is a voltage supply for supplying diallers, can also be used for memory back up because it does not leak any current back into ...
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PBL 385 70 Ordering Information Package Temp. Range Plastic DIP -40 to +70 C Plastic SO -40 to +70 C Plastic SO -40 to +70 C Information given in this data sheet is believed to be accurate and reliable. However ...