CN1453977A - Automatic offhook device for telephone communication - Google Patents

Automatic offhook device for telephone communication Download PDF

Info

Publication number
CN1453977A
CN1453977A CN 02117184 CN02117184A CN1453977A CN 1453977 A CN1453977 A CN 1453977A CN 02117184 CN02117184 CN 02117184 CN 02117184 A CN02117184 A CN 02117184A CN 1453977 A CN1453977 A CN 1453977A
Authority
CN
China
Prior art keywords
resistance
circuit
triode
microprocessor
composite pipe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN 02117184
Other languages
Chinese (zh)
Other versions
CN1210930C (en
Inventor
汪仕文
李永建
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qinghua Tongfang Co Ltd
Original Assignee
Qinghua Tongfang Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qinghua Tongfang Co Ltd filed Critical Qinghua Tongfang Co Ltd
Priority to CN 02117184 priority Critical patent/CN1210930C/en
Publication of CN1453977A publication Critical patent/CN1453977A/en
Application granted granted Critical
Publication of CN1210930C publication Critical patent/CN1210930C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Telephone Function (AREA)

Abstract

The present invention comprises directional circuit formed by diode D1-D4; multiple-unit tube circuit formed by resistance R6, triode T2 and T1; piezo-resistance 2NR; equivalent resistance formed by resistance R4 and R5, DC resistance of audio transformer and microprocessor. Its structure character is as the follows: phone line CJ2 being connected to direction circuit, piezo-resistance 2NR being connected with directional circuit in parallel, directional circuit negative end being connected with earthing and positive end being connected with triode T, emitter in multiple-unit tube circuit which its triode T1 and T2 collectors are connected to equivalent resistance and microprocessor being connected to base of triode T2 through photocouple UT-2.

Description

A kind of automatic offhook device that is used for telephonic communication
Technical field
The present invention relates to a kind of automatic offhook device that is used for telephonic communication, belong to telephone remote control field.
Background technology
The automatic off-hook technology of existing telephonic communication normally utilizes the double-tone frequency power transformer to regulate the resistance value that smart phone inserts telephone network, so that make its impedance and loop current meet the requirement of national standard telephone network.And double-tone frequency power transformer volume is bigger, and does not domesticly produce in batches, needs customization or from ordering abroad.Therefore, the dislodging machine control device of existing smart phone exists cost height, volume big, and perhaps poor safety performance may be damaged the equipment of telephone office, the problem that telephone network is had a negative impact.
Summary of the invention
At above-mentioned the problems of the prior art, the invention provides that a kind of cost is low, security performance good, the automatic offhook device that is used for telephonic communication that telephone network is not exerted an influence.
Technical scheme of the present invention, realize as follows:
The composite pipe circuit that a kind of automatic offhook device that is used for telephonic communication comprises the directional circuit be made up of diode D1-D4, be made up of resistance R 6, triode T2 and T1, piezo-resistance ZNR, the equivalent resistance of forming by the D.C. resistance of resistance R 4 and R5, audio frequency transformer, microprocessor.Its design feature is, telephone wire CJ2 connects directional circuit, the piezo-resistance ZNR directional circuit that inserts in parallel, the directional circuit negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit, the collector electrode of triode T1 and T2 is connected with equivalent resistance in the composite pipe circuit, and microprocessor connects the base stage of triode T2 in the composite pipe circuit by optocoupler U7-2.
The present invention has protected telephone communication device owing to used the make a return journey high voltage interference of telephone wire of piezo-resistance.Also used equivalent resistance to come regulating system to insert the resistance value of telephone network in this device, guaranteed that the direct current in the telephone wire is about 20MA when triode T1 conducting.Avoided the influence of device, reduced the cost of phone dislodging machine control device Be Controlled electrical equipment and telephone network.Audio frequency transformer has been realized the mutual coupling of signals such as DTMF, voice, process simultaneously, and realizes the electrical isolation of telephone wire and microprocessor.
Description of drawings
Accompanying drawing is a circuit connection diagram of the present invention.
Embodiment
Referring to accompanying drawing, the composite pipe circuit 2 that a kind of automatic offhook device that is used for telephonic communication comprises the directional circuit 1 be made up of diode D1-D4, be made up of resistance R 6, triode T2 and T1, piezo-resistance ZNR, by the equivalent resistance 3 that the D.C. resistance of resistance R 4 and R5, audio frequency transformer B1 is formed, model is a 89C52 microprocessor 4.Its design feature is, telephone wire CJ2 connects directional circuit 1, the piezo-resistance ZNR directional circuit 1 that inserts in parallel, directional circuit 1 negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit 2, the collector electrode of triode T1 and T2 is connected with equivalent resistance 3 in the composite pipe circuit 2, and microprocessor 4 is the base stage that the optocoupler U7-2 of TLP521 connects triode T2 in the composite pipe circuit 2 by model.When the pin of microprocessor 4 was high level, 6, the 5 pin conductings of optocoupler U7-2 made the T1 conducting of composite pipe circuit 2.No matter the polarity of telephone wire how, directional circuit 1 guarantees that the emitter of T1 is positive voltage.Piezo-resistance ZNR be for the high-tension interference of removing telephone wire as thunderbolt etc., the protection phone module is unlikely to damage.When the T1 conducting, equivalent resistance 3 guarantees that the direct current in the telephone wire is: about 20MA, realize normal handoff functionality.Audio frequency transformer B1 realizes the mutual coupling of signals such as DTMF, voice, process simultaneously, and realizes the electrical isolation of telephone wire and microprocessor.

Claims (2)

1. an automatic offhook device that is used for telephonic communication comprises the directional circuit of being made up of diode D1-D4 (1), by resistance R 6, the composite pipe circuit (2) that triode T2 and T1 form, piezo-resistance ZNR, by resistance R 4 and R5, the equivalent resistance (3) that the D.C. resistance of audio frequency transformer B1 is formed, microprocessor (4), it is characterized in that, telephone wire CJ2 connects directional circuit (1), the piezo-resistance ZNR directional circuit (1) that inserts in parallel, directional circuit (1) negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit (2), the collector electrode of triode T1 and T2 is connected with equivalent resistance (3) in the composite pipe circuit (2), and microprocessor (4) connects the base stage of triode T2 in the composite pipe circuit (2) by optocoupler U7-2.
2. device as claimed in claim 1 is characterized in that, described microprocessor (4) model is 89C52, and the model of described optocoupler U7-2 is TLP521.
CN 02117184 2002-04-27 2002-04-27 Automatic offhook device for telephone communication Expired - Fee Related CN1210930C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 02117184 CN1210930C (en) 2002-04-27 2002-04-27 Automatic offhook device for telephone communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 02117184 CN1210930C (en) 2002-04-27 2002-04-27 Automatic offhook device for telephone communication

Publications (2)

Publication Number Publication Date
CN1453977A true CN1453977A (en) 2003-11-05
CN1210930C CN1210930C (en) 2005-07-13

Family

ID=29257206

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 02117184 Expired - Fee Related CN1210930C (en) 2002-04-27 2002-04-27 Automatic offhook device for telephone communication

Country Status (1)

Country Link
CN (1) CN1210930C (en)

Also Published As

Publication number Publication date
CN1210930C (en) 2005-07-13

Similar Documents

Publication Publication Date Title
CN102769810A (en) Mobile terminal with a calling misoperation preventive function
CN1210930C (en) Automatic offhook device for telephone communication
CN2549665Y (en) Automatic take-off device for telephone communication
US7755221B2 (en) Electronic device with compound audio interface and power adapter
CN214254885U (en) Short-circuit-proof electronic connector and short-circuit-proof electronic connector
CN209104526U (en) Multi-purpose interface
CN1165467A (en) Terminal equipment
CN216290291U (en) Quick charging circuit module based on gallium nitride
CN2442310Y (en) Data communication interface device of passive telephone line
CN2549670Y (en) Pick-off controller of intelligent telephone
CN213635364U (en) Take audio decoding transmission's fill data line soon
CN215731278U (en) Neutral point grounding reactor with variable impedance
CN2450839Y (en) Cordless telephone with phone interface circuit
CN202197318U (en) Terminal
CN208767240U (en) A kind of onboard surge protector
CN212934880U (en) Plug-in wiring board
CN2530408Y (en) Communication line interface converter
CN201742427U (en) Intelligent-protection interface circuit
CN201063686Y (en) Program controlled exchange subscriber line signal detector
CN207938919U (en) USB female seat, terminal device and USB connector
CN2387651Y (en) Isolating distributing frame protector
CN206471301U (en) A kind of power taking structure of breaker
CN2240214Y (en) Theft-proof device for telephone
CN2185958Y (en) Intercom by using broadcasting line communication
CN1453985A (en) Onhook/offhook controller for intelligent telephone

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C56 Change in the name or address of the patentee

Owner name: TONGFANG CO., LTD.

Free format text: FORMER NAME OR ADDRESS: TSINGHUA TONGFANG CO., LTD.

CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20050713

Termination date: 20170427