pbl38573 ETC-unknow, pbl38573 Datasheet
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pbl38573
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pbl38573 Summary of contents
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Speech Circuit for constant current Description. PBL 38573 is a monolithic integrated speech transmission circuit for use in electronic telephones intended specially for telephone lines with constant current feed. Maximum line current less than 130 mA in DIL ...
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PBL 385 73 Maximum Ratings Parameter Line voltage Line current, continuous DIP package Line current, continuous SO package (depending on mounting) Operating temperature range Storage temperature range No input should be set on higher level ...
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Electrical Characterisics cable and line rectifier unless otherwise specified. Amb Parameter Line voltage Transmitting gain, note 1 No gain regulation Transmitting gain, note 1 With gain regulation Transmitting range of regulation ...
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PBL 385 Mute DCO 7 14-pin DIP Figure 5. Pin configurations. Pin Descriptions: Refer to figure 5. Pin Name Function 1 +L Output of the DC-regulator and transmit ...
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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 PBL38573 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 PBL38573 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 further amplifies 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 ( and b) attn //( attn ( ...
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Battery feed R15 Regulation: 450k 48V, 2 • 200 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 73 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 supplies DCO and V +C. (See fig.18) PBL 385 73 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 ...
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PBL 385 73 Few hints how to widen some of the specification limits. See figure 20. How to increase the maximum allowable line current ? The current capability can be extended by using more sophisticated cooling methods but can also ...
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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 9 and 10) and the second ...
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PBL 385 73 Radio interference originating from mobile phones The problem with direct radiated RFI has accentuated nowadays because of the growing numbers of mobile and especially pocket telephones. Thus it is today rather common that a RF transmitter with ...
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HK 3.9M 4x1N4004 220K 4148 680K + + + 2.2M 0 BC550 VDD 10 HKS CMOS MUTE 9 0. 180K DIALLER 91414 SW1 0V 6 VSS P MODE 13 ...