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参数资料
| 型号： | PBL38813 |
| 厂商： | ERICSSON |
| 英文描述： | Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| 中文描述： | 语音交换与内置免提扬声器放大器电路 |
| 文件页数： | 1/16页 |
| 文件大小： | 299K |
| 代理商： | PBL38813 |
January 1998
Figure 1. Block diagram.
24 pin DIP
PBL 388 13
Voice-switched Speakerphone Circuit
with built in loudspeaker amplifier
24 pin SO
Description.
1
The PBL 388 13 contains all the necessary circuitry, amplifiers, detectors,
comparator and control functions to implement a high performance, voice-switched,
loudspeaking, ”hands-free ” telephone. The gain dynamics (attenuation between
channels) is selectable (25dB or 50dB) via a separate pin. A background noise detector
in the transmitting channel reduces the influence of continuous external noise signals
to the switching .
The PBL 388 13 is designed for telephone systems that are either powered from
the telephone line or from a mains powered constant voltage dc. supply. The circuit
contains a transformerless audio power amplifier with a current supply circuitry
(patented) that eliminates the need of inductors. Automatic volume attenuation in the
power amplifier extends the operating range at low line currents. A special feature in
this circuit is that the power amplifier volume control can be implemented either as an
ac. potentiometer control or as a digital control by a
μ
-processor (dc. control).
Filtering is possible of both, the audio and the speech switching control signals,
in both transmitter and receiver channels.
Key Features
Minimum of external components
needed for function.
Selectable gain dynamics. (25 or 50
dB)
Direct telephone line powered solution
(patented).
Low power consumption:
≈
1mA at 3.3V
(typical) for speech switching, audio
power amplifier quiscent current
≈
1mA.
Drives an 25 - 50 ohm loudspeaker
without a transformer.
Background noise compensation in the
transmitting channel with hold function
at receive.
Input amplifiers of both channels have
balanced inputs.
Exellent noise performance.
Encapsulated in 24 pin plastic ”skinny”
DIP and 24 pin SO .
+
F2
F3
F6
F5
–
F1
+
PBL 388 13
F4
22
21
3
1
2
7
6
8
9
13
14
11
23
16
17
18
20
24
15
4
+
–
–
+
19
10
12
Ref.
5
Control
PBL38813
PBL38813
相关PDF资料 |
PDF描述 |
|---|---|
| PBL388131N | Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| PBL388131SO | Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| PBL38814 | Voice - switched 2-channel Circuit with loudspeaker amplifier |
| PBL388141N | Voice - switched 2-channel Circuit with loudspeaker amplifier |
| PBL388141SO | Voice - switched 2-channel Circuit with loudspeaker amplifier |
相关代理商/技术参数 |
参数描述 |
|---|---|
| PBL388131N | 制造商:ERICSSON 制造商全称:Ericsson 功能描述:Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| PBL388131SO | 制造商:ERICSSON 制造商全称:Ericsson 功能描述:Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| PBL388131SOT | 制造商:ERICSSON 制造商全称:Ericsson 功能描述:Voice-switched Speakerphone Circuit with built in loudspeaker amplifier |
| PBL38814 | 制造商:ERICSSON 制造商全称:Ericsson 功能描述:Voice - switched 2-channel Circuit with loudspeaker amplifier |
| PBL388141N | 制造商:ERICSSON 制造商全称:Ericsson 功能描述:Voice - switched 2-channel Circuit with loudspeaker amplifier |
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