pbl38571 ETC-unknow, pbl38571 Datasheet
pbl38571
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pbl38571 Summary of contents
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Description. PBL 38571 is a monolithic integrated speech transmission circuit for use in electronic telephones and as DECT line interface with balanced in - and output designed to accomodate either a low impedance dynamic microphone or an electret ...
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PBL 385 71 Maximum Ratings Parameter Line voltage Line current, continuous, DIP (batwing) package Line current, continuous, SO (batwing) package (dependent on mounting) Operating temperature range Storage temperature range No input should be set on ...
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Electrical Characterisics cable and line rectifier unless otherwise specified. Amb Parameter Line voltage Transmitting gain, note 1 No gain regulation, low mode Transmitting gain, note 1 With gain regulation Transmitting range ...
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PBL 385 Mute 16-pin BW DIP Figure 5. Pin configurations. Pin Descriptions Refer to figure 5. Pin Name Function 1 +L Output of the ...
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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 gro- und (-line), this feature differs it from bridge type solutions.To set the parameters in the following order will result ...
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... V 1 telephoneline line Microphone amplifier The microphone amplifier in PBL38571 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 9. Microphone amplifier output clipping. Transmitter amplifier The transmitter amplifier in PBL38571 consists of three stages. The first stage is an amplitude limiter for the input signal at TI, in order to prevent the transmitted signal to exceed a certain set level and cause distortion. The second stage amplifies further the signal from the first and adds level from an internal DC-regulation loop in order to give the required DC characteristic to the telephone set ...
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PBL 385 (b) ( and b) attn //( attn (d) (e) C ...
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Battery feed R1 Regulation: 48V, 2 • 200 450k 48V, 2 • 400 48V, 2 • 800 Sweden, apply for spec. application. No regulation: All feedings: Set for low gain Set for high gain 75k What is balancing the side ...
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PBL 385 71 Note that the signals at points a. and b. are 180 degrees off phase Zbal Note #1 R7 Zbal Note#2 The ac-signal at point c. is now 1/10 of the signal on ...
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Power supply V +C. (See fig.18) PBL 385 71 generates its own DC supply V +C dependent of line current with an internal shunt regulator. This regulator senses the line voltage V L via R 3 and line current via ...
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PBL 385 71 Short about Radio Frequency Interference RFI. HF suppression at the microphone in- put. The HF-signal at the microphone input can be seen composed as of two components. One component being the differential (between pins 10 and 11) ...
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Radio interference originating from mobile phones The problem with direct radiated RFI has accentuated lately because of the growing numbers of mobile and especially pocket telephones. Thus it is today rather com- mon that a RF transmitter with output power ...
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PBL 385 Telephone system grounded Mains grounded Figure 24. Principal balanced solution for a transformerless line interface that can be used in case of two different ground systems with low disturbance levels. Information given ...