pbl388141sot ETC-unknow, pbl388141sot Datasheet
pbl388141sot
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pbl388141sot Summary of contents
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Voice - switched 2-channel Circuit with Description. The PBL 388 14 contains all the necessary circuitry, amplifiers, detectors, comparator and control functions to implement a high performance voice switched handsfree two- way communication system. The gain dynamics (attenuation between channels) ...
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PBL 388 14 Maximum Ratings Parameter Speech switch supply current Speaker amplifier supply current Voltage pin 1-14 Operating temperature Storage temperature + V + 100 F/16V out Txout ...
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Electrical Characteristics kHz = CTR TxDet I =1.0mA unless otherwise noted. D Parameter Speech control section Terminal voltage Internal reference voltage, V Ref Frequency response for ...
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PBL 388 14 Parameter N leakage current (hold), I Det NDet N swing relative Det Ref NDet CMP (comparator) sensitivity, transmit (Tx) mode to receive (Rx) mode or vice versa CTR voltage for 25 dB dynamics, ...
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F2out 3 4 Txout 5 TxDetin 6 TxDetout Ref Det 8 CMP 9 RxDetout 10 RxDetin 11 Rxout 12 24 pin DIP Figure 4. Pin configuration. Pin Descriptions Refer to figure 6. (24 pin ...
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PBL 388 14 + GND A LSP CTR 4 T xout xin xin ...
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Figure 7. Transmitter channel input amplifier used to suppress ripple in the mic. supply. (CMRR 100k Figure 8. Transmitter and receiver channel rectifier characteristics. Figure 9. Relationship ...
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PBL 388 14 dB Transmit ____ gain = =V+ CTR =open CTR -60 -40 -20 Figure 11. Transmit and receive gain as a function of V Rxdet Txdet A B Full recieve level ...
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Transmitter channel output 24 CTR Tx out + Mic. C Figure 14. Speech switching arrangement. decreases with factor ...
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PBL 388 14 Loudspeaker amplifier The loudspeaker amplifier drives directly impedance loudspeaker. The single ended loudspeaker amplifier has an internal gain regulation that prevents distortion in case of insufficient supply voltage. The loudspeaker volume control can ...
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Tx signal 18 68nF 68nF + 16 100 150nF 820 2 820 150nF MIC. 6.8nF Figure 18. Application with ac. volume control. 22 PBL 388 14 19 15n 10 20 Figure 19. External power amplifier + 100 ...
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PBL 388 14 Hints how to design a handsfree system with PBL 388 14. To design the speech control function, seven different signal paths have to be considered and understood. See fig. 28. The signal paths the acoustic ...
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If a simple telephone casing is considered, it could be a box with a large hole for the loudspeaker and a small hole for the microphone. This would normally not function. The acoustical coupling would be much to high. ...
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PBL 388 14 switching a lot if the telephone is placed in a noisy surrounding. It can not be required that the other party has to know that he is talking with somebody with a handsfree telephone in a noisy ...