CN103581449B - A kind of analog telephone access device - Google Patents
A kind of analog telephone access device Download PDFInfo
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- CN103581449B CN103581449B CN201310471217.6A CN201310471217A CN103581449B CN 103581449 B CN103581449 B CN 103581449B CN 201310471217 A CN201310471217 A CN 201310471217A CN 103581449 B CN103581449 B CN 103581449B
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- 238000004891 communication Methods 0.000 abstract description 8
- 238000012423 maintenance Methods 0.000 abstract description 5
- 238000000034 method Methods 0.000 description 36
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- 230000009897 systematic effect Effects 0.000 description 34
- 230000001681 protective effect Effects 0.000 description 6
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Abstract
本发明公开了一种模拟电话接入设备，属于通信领域。所述设备包括：电话处理芯片，用于检测第一电话的摘挂机、控制第一电话振铃、将双音多频信号转换为数字信号、以及对语音信号进行电压适配、二四线转换、模数转换和数模转换，第一电话为与设备连接的模拟电话，双音多频信号为第一电话拨号时产生的高低频组合信号；极性倒换模块，用于当第一电话挂机时，发送极性倒换信号；复杂可编程逻辑器件模块，用于为电话处理芯片提供时序、对语音信号进行时分复用和解复用；最小系统模块，用于控制电话处理芯片、极性倒换模块和复杂可编程逻辑器件模块、以及接收极性倒换信号，第二电话为与第一电话通话的电话。本发明设备体积小，可靠性高，维护成本低。
The invention discloses an analog telephone access device, which belongs to the communication field. The device includes: a telephone processing chip, which is used to detect the on-hook of the first telephone, control the ringing of the first telephone, convert the dual-tone multi-frequency signal into a digital signal, and perform voltage adaptation and two-to-four-wire conversion on the voice signal. , analog-to-digital conversion and digital-to-analog conversion, the first phone is an analog phone connected to the device, and the dual-tone multi-frequency signal is a combination of high and low frequencies generated when the first phone dials; the polarity inversion module is used when the first phone hangs up When the polarity switching signal is sent; the complex programmable logic device module is used to provide timing for the telephone processing chip, time-division multiplexing and demultiplexing of the voice signal; the smallest system module is used to control the telephone processing chip and the polarity switching module and the complex programmable logic device module, and receiving the polarity switching signal, the second phone is the phone talking with the first phone. The equipment of the invention has small volume, high reliability and low maintenance cost.
Description
Technical field
The present invention relates to the communications field, particularly a kind of analog telephone access device.
Background technology
During owing to carrying out voice communication, analog telephone produces and the voice signal of process is analog signal, and the voice signal of stored-program control exchange process is digital signal, and therefore analog telephone needs to be connected with stored-program control exchange by analog telephone access device.Wherein, stored-program control exchange is used for realizing network exchange, with transmission of speech signals, analog telephone access device is used for processing voice signal, the voice signal from analog telephone that stored-program control exchange is received is digital signal, and the voice signal from stored-program control exchange that analog telephone receives is analog signal.
Existing analog telephone access device comprises some discrete modules, and each module is made up of multiple chip.Such as adopt several chips to form a logic processing module, this logic processing module is used for providing sequential and carrying out time division multiplexing and demultiplexing to voice signal.
Realizing in process of the present invention, inventor finds that prior art at least exists following problem:
In existing analog telephone access device, different functions is completed by different separate modules, and each module is made up of multiple chip, and therefore whole analog telephone access device is bulky, and the huge equipment dependability that causes of equipment required device quantity is lower, maintenance cost is high.
Summary of the invention
In order to solve the problem that prior art is bulky, reliability is low and maintenance cost is high, embodiments provide a kind of analog telephone access device.Described technical scheme is as follows:
Embodiments provide a kind of analog telephone access device, described equipment comprises:
Phone process chip, for detect the first phone dislodging machine, control described first phone ringing, touch-tone signal be converted to digital signal and voltage adaptation, two or four lines conversions, analog-to-digital conversion and digital-to-analogue conversion carried out to voice signal, described first phone is the analog telephone with described equipment connection, the low-and high-frequency composite signal produced when described touch-tone signal is described first dialing;
Polarity reversal module, for when described first phone on-hook, sends the polarity reversal signal for representing described first phone on-hook;
CPLD module, for providing sequential for described phone process chip, carry out time division multiplexing and demultiplexing to described voice signal;
Minimum systematic module, for the polarity reversal signal controlling described phone process chip, described polarity reversal module and described CPLD module and receive for representing the second phone on-hook, described second phone is the phone with described first telephone relation;
Described phone process chip comprises:
Subscriber line interface unit, for detect described first phone dislodging machine, control described first phone ringing, voltage adaptation carried out to described voice signal;
Coder unit, for carrying out two or four line conversions, analog-to-digital conversion and digital-to-analogue conversion to described voice signal;
Digital signal processing unit, for being converted to digital signal and controlling described subscriber line interface unit and described coder unit by touch-tone signal;
Power subsystem, for providing power supply for the first phone;
CPLD module interface, for providing the interface with described CPLD model calling for described digital signal processing unit;
Minimum systematic module interface, for providing the interface be connected with described minimum systematic module for described digital signal processing unit.
In the first possible implementation of the present invention, described CPLD module comprises:
CPLD chip, for providing sequential for described phone process chip, carry out time division multiplexing and demultiplexing to described voice signal;
First clock circuit, for providing clock signal for described CPLD chip.
In the implementation that the second of the present invention is possible, described minimum systematic module comprises:
Central processing unit, for controlling described phone process chip, described polarity reversal module and described CPLD module;
Memory, for storing the program and instruction that control described phone process chip, described polarity reversal module and described CPLD module;
Second clock circuit, for providing clock signal for described central processing unit.
Alternatively, described memory comprises one or more in read-only memory, random asccess memory and flash memory.
Alternatively, described minimum systematic module also comprises watchdog circuit for resetting and/or manual reset circuit.
Alternatively, described minimum systematic module also comprises for downloading debugging routine and the ethernet interface circuit carrying out Internet protocol call.
In the third possible implementation of the present invention, described equipment also comprise for correct described minimum systematic module output signal address and data/address bus buffer module.
In the 4th kind of possible implementation of the present invention, described equipment also comprises the protective circuit for preventing described equipment to be subject to extraneous affected by high.
In the 5th kind of possible implementation of the present invention, described equipment also comprises for ensureing as described equipment provides the plug-and-play circuit module of stabilized power supply.
The beneficial effect that the technical scheme that the embodiment of the present invention provides is brought is:
Adopt phone process chip, polarity reversal module, CPLD module and minimum systematic module composition analog telephone input equipment, because this chip of phone process chip just can complete in existing skill equipment the function needing multiple module comprising multiple chip to complete, therefore the volume of equipment reduces greatly, and because the integrated level of phone process chip is very high, coordinate compared with a functions of modules with needing multiple chip in existing equipment, reliability improves greatly, and maintenance cost is lower.
Accompanying drawing explanation
In order to be illustrated more clearly in the technical scheme in the embodiment of the present invention, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the structural representation of a kind of analog telephone access device that the embodiment of the present invention provides;
Fig. 2 is the structural representation of the phone process chip that the embodiment of the present invention provides;
Fig. 3 is the structural representation of the protective circuit that the embodiment of the present invention provides.
Embodiment
For making the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, embodiment of the present invention is described further in detail.
Embodiment
Embodiments provide a kind of analog telephone access device, see Fig. 1, this equipment comprises phone process chip 1, polarity reversal module 2, CPLD (ComplexProgrammableLogicDevice, CPLD) module 3 and minimum systematic module 4.
In the present embodiment, phone process chip 1 for, to the first phone detect the first phone dislodging machine, control the first phone ringing, DTMF (DualToneMultifrequency, dual-tone multifrequency) signal be converted to digital signal and voltage adaptation, two or four lines conversions, analog-to-digital conversion and digital-to-analogue conversion carried out to voice signal.First phone is the analog telephone with this equipment connection, the low-and high-frequency signal combination signal produced when dtmf signal is the first dialing.
Polarity reversal module 2, for when the first phone on-hook, sends the polarity reversal signal for representing the first phone on-hook.
CPLD module 3 for, for phone process chip 1 provides sequential, carries out time division multiplexing and demultiplexing to voice signal.
Minimum systematic module 4 for, the polarity reversal signal controlling phone process chip 1, polarity reversal module 2 and CPLD module 3 and receive for representing the second phone on-hook, the second phone is the phone with the first telephone relation.
It should be noted that, voltage due to the voice signal from analog telephone input analog telephone access device is greater than the operating voltage of chip usually, voltage as voice signal is 12V (volt), the operating voltage of chip is 3.3V, therefore phone process chip 1 pair of voice signal carries out voltage adaptation, and the voltage of voice signal can be made to reduce to the operating voltage of chip.Receive due to analog signal and send on the loop of all two wires, Shi mono-tunnel compositions, digital signal transmitting-receiving respectively on the loop of two two wires, tunnel compositions (being four lines altogether), therefore the voice signal of phone process chip 1 to simulation carries out two or four lines conversions, can so that the process of voice signal of logarithm word.
In actual applications, phone process chip 1 is connected with CPLD module 3, minimum systematic module 4 respectively, polarity reversal module 2 is connected with minimum systematic module 4, connection data bus and address bus between minimum systematic module 4 and CPLD module 3, CPLD module 3 is according to the chip selection signal on address bus, send the control signal on data/address bus to phone process chip 1, chip selection signal is for selecting the analog telephone 5 controlled, and control signal is used for control simulation phone 5.
Analog telephone 5 is connected with phone process chip 1, and the quantity of the analog telephone 5 be connected with phone process chip 1 is subject to the quantitative limitation of phone process chip 1 number of ports.CPLD module 3 is connected with stored-program control exchange 6 respectively with minimum systematic module 4, transmission of speech signals between CPLD module 3 and stored-program control exchange 6, the control signal of transport voice communications between minimum systematic module 4 and stored-program control exchange 6.
In a kind of implementation of the present embodiment, see Fig. 2, phone process chip 1 can comprise:
SLIC (SubscriberLineInterface, Subscriber Line Interface Circuit) unit 11, for detect the first phone dislodging machine, control the first phone ringing, voltage adaptation carried out to voice signal;
CODEC (Coder-Decoder, coder) unit 12, for carrying out two or four line conversions, analog-to-digital conversion and digital-to-analogue conversion to voice signal;
DSP (DigitalSignalProcessing, Digital Signal Processing) unit 13, for being converted to digital signal and control SLIC unit and CODEC unit by dtmf signal;
Power subsystem 14, for providing power supply for the first phone;
CPLD module interface 15, for providing the interface be connected with CPLD module 3 for DSP unit;
Minimum systematic module interface 16, for providing the interface be connected with minimum systematic module 4 for DSP unit.
Particularly, DSP unit 13 is connected with SLIC unit 11, CODEC unit 12, CPLD module interface 15, minimum systematic module interface 16 respectively, and power subsystem 14 is connected with SLIC unit 11.
Alternatively, SLIC unit 11 can comprise pre-driver 111 for carrying out voltage adaptation to voice signal, for detect the first phone dislodging machine monitoring subelement 112, for controlling PWM (PulseWidthModulation, the pulse width modulation) controller 113 of the first telephony voltages.
Alternatively, CODEC unit 12 can comprise a CODEC subelement 121 for carrying out analog-to-digital conversion and digital-to-analogue conversion to voice signal and the 2nd CODEC subelement 122.Analog-to-digital conversion or digital-to-analogue conversion is carried out owing to adopting a CODEC subelement 121 and the 2nd CODEC subelement 122 pairs of voice signals simultaneously, therefore, while a CODEC subelement 121 and the 2nd CODEC subelement 122 pairs of voice signals carry out analog-to-digital conversion and digital-to-analogue conversion, two or four line conversions are completed.
Alternatively, power subsystem 14 can be direct current transducer.
It should be noted that, the voltage of the first phone ringing is generally 75V, supply voltage is generally 12V, therefore DSP unit 13 can transmit control signal to PWM controller 13, PWM controller sends and sends pwm signal to power subsystem 14, makes power subsystem 14 provide ring required voltage for the first phone, thus controls the first phone ringing, therefore do not need to be that the first phone ringing arranges special power supply, facilitate the use of equipment.
Preferably, phone process chip 1 can be SI32260, greatly saves the volume of equipment, improves the reliability of equipment.
In the another kind of implementation of the present embodiment, CPLD module 3 can comprise:
CPLD chip, for providing sequential, carrying out time division multiplexing and demultiplexing to voice signal for phone process chip;
First clock circuit, for providing clock signal for CPLD chip.
In the present embodiment, CPLD chip is connected with the first clock circuit.
Preferably, CPLD chip can be EPM7256144, greatly saves the volume of equipment, improves the reliability of equipment.
Particularly, the first clock circuit is the crystal oscillating circuit of 16.384MHz (megahertz).
In another implementation of the present embodiment, minimum systematic module 4 can comprise:
CPU (CentralProcessingUnit, central processing unit), for phone process chip 1, polarity reversal module 2 and CPLD module 3;
Memory, for storing the program and instruction that control phone process chip 1, polarity reversal module 2 and CPLD module 3;
Second clock circuit, for providing clock signal for CPU.
In the present embodiment, CPU is connected with memory, second clock circuit respectively.
Particularly, CPU can be MPC866, and second clock circuit comprises crystal oscillating circuit and the phase-locked loop circuit of 10MHz.
Preferably, memory can comprise one or more in ROM (ReadOnlyMemory, read-only memory), RAM (RandomAccessMemory, random asccess memory) and flash memory.ROM is used for storage system program, RAM is for storing the result of CPU computing, and flash memory, for storing start-up routine, can make system program preserve in memory always, the result of computing changes along with the difference of input cpu signal, and start-up routine is convenient amendment as required.
Particularly, ROM can be the SST39VF040 of 4M (million) for capacity, and the HY57V561620 that RAM can be 16 by two panels data width forms, and flash memory can be TE28F0420.
Preferably, minimum systematic module 4 can also comprise watchdog circuit for resetting and/or manual reset circuit, and watchdog circuit and/or manual reset circuit are connected with CPU.Reset when CPU operation troubles, CPU can be made to restart, recover normal operating conditions.Wherein, watchdog circuit is used for automatically reseting, and manual reset circuit is used for artificial reset.
Particularly, the chip of watchdog circuit can be MAX706.
Alternatively, minimum systematic module 4 can also comprise for downloading debugging routine and carrying out IP (InternetProtocol, Internet protocol) ethernet interface circuit conversed, ethernet interface circuit is connected with CPU, and analog telephone 5 can also be conversed with IP phone.
Particularly, ethernet interface circuit comprises PHY (Physical, physical layer) circuit and Ethernet transformation device.
More specifically, the chip of PHY circuit is RTL8201.
In another implementation of the present embodiment, this equipment can also comprise for correct minimum systematic module 4 output signal address and data/address bus buffer module, address and data/address bus buffer module are arranged on address bus and data/address bus, be connected with minimum systematic module 4 and CPLD module 3 respectively, ensure the accuracy that minimum systematic module 4 outputs signal, and then guarantee equipment reliability of operation.
Particularly, address and data/address bus buffer module can comprise the chip that two panels model is 74FCT163245.
In another implementation of the present embodiment; this equipment can also comprise the protective circuit for preventing equipment to be subject to extraneous affected by high (as thunderbolt, high-voltage line); minimum systematic module 4 is connected with stored-program control exchange 6 by protective circuit with CPLD module 3, the normal operation of proterctive equipment.
Alternatively; see Fig. 3; protective circuit can comprise four CurrentMirror (mirror image power supply), respectively with a CurrentMirror100, the 2nd CurrentMirror200, the 3rd CurrentMirror300 and the 4th CurrentMirror400.Each CurrentMirror includes protect IC, protective resistance and triode, and the base stage of triode is connected with one end of protect IC, and the transmitting collection of triode is connected with one end of resistance.
Particularly, the collector electrode of the first triode VTI in the one CurrentMirror is connected with the collector electrode of the second triode VT2 in the 2nd CurrentMirror, and the collector electrode of the 3rd triode VT3 in the 3rd CurrentMirror is connected with the collector electrode of the 4th triode VT4 in the 4th CurrentMirror.The other end ground connection of the 3rd resistance R3 in the other end of the first resistance R1 in the one CurrentMirror and the 3rd CurrentMirror, the other end of the second resistance R2 in the 2nd CurrentMirror is connected with the other end of the 4th resistance R4 in the 4th CurrentMirror.The other end of the first protect IC IC1 in the one CurrentMirror is connected with the other end of the 4th protect IC IC4 in the other end of the 3rd protect IC IC3 in the other end of the second protect IC IC2 in the 2nd CurrentMirror, the 3rd CurrentMirror, the 4th CurrentMirror respectively.
More specifically, the model of protect IC can be TISP61089BDR.
In another implementation of the present embodiment, this equipment can also comprise for ensureing that, for described equipment provides the plug-and-play circuit module of stabilized power supply, the modules such as minimum systematic module 4 or chip are connected with power supply by plug-and-play circuit module.
Particularly, plug-and-play circuit module can comprise the chip that model is TPS2421.
In actual applications, the various piece of this equipment is arranged on different veneers respectively, is connected between veneer by backboard, and backboard can select the connector of 100 cores.
Simply introduce the operation principle of the analog telephone access device that the embodiment of the present invention provides below:
When the first phone is caller phone, monitoring subelement 112 detects the first phone off-hook, and reported to minimum systematic module 4 from minimum systematic module interface 16 by DSP unit 13, and then inform stored-program control exchange 6, stored-program control exchange 6 loopback dialing tone gives the first phone.First phone dials, the dtmf signal that dialing produces is converted to digital signal by DSP unit 13, and report from minimum systematic module interface 16 to minimum systematic module 4, and then by stored-program control exchange 6 enquiry number for the busy-idle condition of the second dialled the number phone and to the corresponding bell sound of analog telephone 5 loopback.When after the second phone off-hook, between the first phone and the second phone, establish voice communication.
Or, when the first phone is called phone, DSP unit 13 transmits control signal to PWM controller 113, PWM controller 113 sends pwm signal to power subsystem 14, power subsystem 14 is made to provide the voltage of 75V for the first phone, first phone ringing, when monitoring subelement 112 detects the first phone off-hook, voice communication is set up.
The voice signal that first phone sends carries out voltage adaptation by pre-driver 111, two or four line conversion and analog-to-digital conversion are carried out by a CODEC subelement 121 and the 2nd CODEC subelement 122, after CPLD module 3 carries out time division multiplexing, sent to the second phone by stored-program control exchange 6.The voice signal that the second phone that stored-program control exchange 6 receives sends carries out demultiplexing by CPLD module 3, after a CODEC subelement 121 and the 2nd CODEC subelement 122 carry out digital-to-analogue conversion and the conversion of two or four lines, by the first phone reception.Whole process is controlled by CPLD module 3 by minimum systematic module 4, and by CPLD module 3 for phone process chip 1 provides sequential.
When monitoring subelement 112 and the first phone on-hook being detected, minimum systematic module 4 controls polarity reversal module 2 and sends polarity reversal signal for representing the first phone on-hook, and the voice communication between the first phone and the second phone terminates.Or when stored-program control exchange 6 is by when being used for representing that the polarity reversal signal of the second phone on-hook sends to minimum systematic module 4, the voice communication between the first phone and the second phone terminates.
The embodiment of the present invention adopts phone process chip, polarity reversal module, CPLD module and minimum systematic module composition analog telephone input equipment, because this chip of phone process chip just can complete in existing skill equipment the function needing multiple module comprising multiple chip to complete, therefore the volume of equipment reduces greatly, and because the integrated level of phone process chip is very high, coordinate compared with a functions of modules with needing multiple chip in existing equipment, reliability improves greatly, and maintenance cost is lower.
One of ordinary skill in the art will appreciate that all or part of step realizing above-described embodiment can have been come by hardware, the hardware that also can carry out instruction relevant by program completes, described program can be stored in a kind of computer-readable recording medium, the above-mentioned storage medium mentioned can be read-only memory, disk or CD etc.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (9)
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| CN201213282Y (en) * | 2008-05-30 | 2009-03-25 | 清华大学 | A telephone remote control and alarm device |
| CN201563067U (en) * | 2009-11-03 | 2010-08-25 | 深圳市共进电子有限公司 | Power supply adapter matched with IP telephone set and VOIP access equipment |
| CN102348026A (en) * | 2010-07-30 | 2012-02-08 | 国基电子（上海）有限公司 | Telephone network communication device and network switching method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7269524B1 (en) * | 2006-06-30 | 2007-09-11 | Inapac Technology, Inc. | Delay lock loop delay adjusting method and apparatus |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2181143Y (en) * | 1994-01-09 | 1994-10-26 | 周运信 | Alarm device for telephone when placed on non-right position |
| CN201213282Y (en) * | 2008-05-30 | 2009-03-25 | 清华大学 | A telephone remote control and alarm device |
| CN201563067U (en) * | 2009-11-03 | 2010-08-25 | 深圳市共进电子有限公司 | Power supply adapter matched with IP telephone set and VOIP access equipment |
| CN102348026A (en) * | 2010-07-30 | 2012-02-08 | 国基电子（上海）有限公司 | Telephone network communication device and network switching method |
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