CN203788392U

CN203788392U - Hdmi signal processing circuit

Info

Publication number: CN203788392U
Application number: CN201320834837.7U
Authority: CN
Inventors: 王绍惇; 王林
Original assignee: Leshi Zhixin Electronic Technology Tianjin Co Ltd
Current assignee: Leshi Zhixin Electronic Technology Tianjin Co Ltd
Priority date: 2013-12-13
Filing date: 2013-12-13
Publication date: 2014-08-20
Anticipated expiration: 2023-12-13

Abstract

The application discloses a HDMI signal processing circuit applied on terminal equipment; the HDMI signal processing circuit comprises a HDMI interface, a power supply module, a control unit and a plurality of resistors; the power supply module is coupled to a hot plugging detection pin, a serial clock line pin and a serial data line pin of the HDMI interface through the resistors; the control unit is respectively coupled to the HDMI interface and the power supply module so as to receive an enable signal of the HDMI interface, and a control signal can be correspondingly sent to the power supply module, so the power supply module can correspondingly adjust level changes of the hot plugging detection pin; a hot plugging detection signal can be actively sent to the source end equipment, the source end equipment can carry out follow up signal transmission step according to HMDI protocol, so signal transmission between the source end equipment and the terminal equipment can be ensured without being affected by power supply pin damages on a HDMI joint or the interface.

Description

HDMI signal processing circuit

Technical field

The application relates to signal process field, is specifically related to a kind of HDMI signal processing circuit.

Background technology

HDMI (High Definition Multimedia Interface) (High-definition Multimedia Interface, hereinafter to be referred as HDMI) be a kind of video/audio coffret of total digitalization, in order to the transmission medium as vision signal and audio signal between source equipment (source) and terminal equipment (sink), such as the transmission medium as audio-video signal between the terminal equipments such as the source equipment such as Set Top Box (set-top box), DVD player, computer or game machine and television set and projector.

The greatest feature of HDMI interface is that integration vision signal and audio signal are together transmitted, and adopts the digital data transfer mode of non-compression, can effectively reduce the signal causing in numeral and analog-converted and disturbs and decay.The HDMI joint of standard has 19 pins, wherein except serial time clock line (Serial Clock Line, SCL) pin and serial data line (Serial Data Line, SDA) outside pin, also have 3 pins can make whether exact connect ion and can mutually transmit ditch messenger of source equipment and terminal equipment confirmation HDMI interface to each other, these 3 pins are respectively consumer electronics and control Consumer Electronics Control, CEC) pin, hot plug detecting (Hot Plug Detect, hereinafter to be referred as HPD) pin and DDC (Display Data Channel, DDC) pin.In addition, also has 1 power pins, in order to corresponding pin in the HDMI interface from source supply of equipment power supply to terminal equipment, making the HPD signal of the HDMI interface of terminal equipment is high level from low transition, thereby confirms source equipment accessed terminal equipment.

Yet power pins is configured near HDMI interface and the outermost position of joint, causes power pins to be easily subject to improper twisting at joint; Or be subject to electrostatic interaction or coupled under the situation of the improper operations such as equipment of overload being short-circuited, HPD signal cannot be triggered, and cause terminal equipment to think that source equipment not yet accesses.

In the case, due on HDMI joint or interface except power pins, it is normal that the function of other pins still maintains, but but because the damage of power pins causes other pins cannot normal operation between terminal equipment and source equipment, and cause on terminal equipment without picture disply, so, not only in the use of terminal equipment and source equipment quite outside inconvenience, in the maintenance of HDMI Jie Head or interface, also form waste with replacing with simultaneously.

Summary of the invention

The application's technical problem to be solved is to provide a kind of HDMI signal processing circuit, the hot plug detecting pin of power supply to HDMI interface is provided on terminal equipment by power module, and triggering hot plug detection signal, and then make can not be subject between source equipment and terminal equipment the impact that power pins is damaged, and can carry out according to HDMI agreement the mutual transmission of signal, thereby the power pins that has solved general HDMI interface or joint is damaged, institute causes cannot carrying out between terminal equipment and source equipment the problem of the signal transmission of HDMI agreement.

In order to address the above problem, the application has disclosed a kind of HDMI signal processing circuit, is applicable on terminal equipment, makes terminal equipment be coupled to source equipment by HDMI signal processing circuit.HDMI signal processing circuit comprises HDMI interface, power module and control unit.HDMI interface comprises hot plug detecting pin, serial clock wire pin and serial data wire pin, power module is coupled to HDMI interface, and control unit is respectively coupled to HDMI interface and power module, wherein control unit is in order to receive the enable signal of HDMI interface, and correspondence sends a control signal to power module; Power module regulates the level of hot plug detecting pin to change according to control signal, the corresponding level of control unit is changed by hot plug and detect pin transmission hot plug detection signal to source equipment, thereby make source equipment by the expanded display recognition data of serial clock wire pin and serial data wire pin reading terminal equipment.

Compared with prior art, the application can obtain and comprise following technique effect:

The application's HDMI signal processing circuit, at source equipment, pass through after HDMI interface access terminal equipment, when control unit receives after the enable signal of HDMI interface, by power module, provide the hot plug detecting pin of power supply to HDMI interface, make the quilt triggering initiatively on terminal equipment of hot plug detection signal, thereby make can carry out signal transmission according to HDMI agreement between source equipment and terminal equipment.Therefore, no matter whether the power pins of HDMI interface or joint is damaged, and all can make terminal equipment confirm the annexation between itself and source equipment, and reach the object that presents image frame at terminal equipment.So, not only in the use of terminal equipment and source equipment, outside suitable facility, also can significantly reduce maintenance and the replacement cost of HDMI joint or interface simultaneously.

Accompanying drawing explanation

Accompanying drawing described herein is used to provide further understanding of the present application, forms the application's a part, and the application's schematic description and description is used for explaining the application, does not form the improper restriction to the application.In the accompanying drawings:

Fig. 1 is the block schematic diagram of the HDMI signal processing circuit of the application the first embodiment.

Fig. 2 is the circuit diagram of the hot plug detecting pin of the application the first embodiment.

Fig. 3 is the serial clock wire pin of the application the first embodiment and the circuit diagram of serial data wire pin.

Fig. 4 and Fig. 5 are the flow chart of the HDMI signal processing method of the application the first embodiment.

Fig. 6 is the block schematic diagram of the HDMI signal processing circuit of the application the second embodiment.

Fig. 7 is the circuit diagram of the hot plug detecting pin of the application the second embodiment.

Fig. 8 is the serial clock wire pin of the application the second embodiment and the circuit diagram of serial data wire pin.

Fig. 9 and Figure 10 are the flow chart of the HDMI signal processing method of the application the second embodiment.

Embodiment

To coordinate drawings and Examples to describe the application's execution mode in detail below, by this application's implementation procedure how application technology means solve technical problem and reach technology effect can be fully understood and be implemented according to this.

As used some vocabulary in the middle of specification and claim, censure specific components.Those skilled in the art should understand, and hardware manufacturer may be called same assembly with different nouns.This specification and claims are not used as distinguishing the mode of assembly with the difference of title, but the difference in function is used as the criterion of distinguishing with assembly.If " comprising " mentioned in the middle of specification and claim is in the whole text an open language, therefore should be construed to " comprise but be not limited to "." roughly " refer to that in receivable error range, those skilled in the art can solve the technical problem within the scope of certain error, reach described technique effect substantially.In addition " couple ", or " electric connection " word comprises directly any and electric property coupling means indirectly at this.Therefore, if describe a first device in literary composition, be coupled to one second device, represent that described first device can directly be electrically coupled to described the second device, or be indirectly electrically coupled to described the second device by other devices or the means that couple.Specification subsequent descriptions is for implementing the application's better embodiment, and right described description is to illustrate that the application's rule is object, not in order to limit the application's scope.The application's protection range is when being as the criterion depending on the claims person of defining.

Also it should be noted that, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thereby the process, method, commodity or the system that make to comprise a series of key elements not only comprise those key elements, but also comprise other key elements of clearly not listing, or be also included as the intrinsic key element of this process, method, commodity or system.The in the situation that of more restrictions not, the key element being limited by statement " comprising ... ", and be not precluded within process, method, commodity or the system that comprises described key element and also have other identical element.

the application's application scenarios

While carrying out signal transmission according to HDMI agreement between terminal equipment and source equipment, the power pins of the HDMI interface on terminal equipment is damaged or when connecting the power pins of the HDMI joint of terminal equipment and damage, cause terminal equipment detecting less than the power supply signal of source equipment, and can not corresponding send hot plug detection signal, thereby make between terminal equipment and source equipment to be applicable to cannot proper communication time the application's scheme.

embodiment describes

As shown in Figure 1, the HDMI signal processing circuit 10 that the application the first embodiment discloses, be applicable on terminal equipment 20, make terminal equipment 20 be coupled to source equipment 30 by HDMI signal processing circuit 10, wherein terminal equipment 20 can be but be not limited to the image playback equipments such as television set and projector, and source equipment 30 can be the audio frequency and video output equipments such as Set Top Box, DVD player, computer or game machine, in the present embodiment, to take terminal equipment 20 as television set, source equipment 30 be Set Top Box as an example, but not as limit.

Please refer to Fig. 1 to Fig. 3, HDMI signal processing circuit 10 comprises HDMI interface 110, power module 120 and control unit 130.

HDMI interface 110 comprises hot plug detecting (Hot Plug Detect, HPD) pin 111, serial time clock line (Serial Clock Line, SCL) pin 112 and serial data line (Serial Data Line, SDA) pin 113, be respectively coupled to control unit 130, wherein hot plug detecting pin 111 comprises signal end HPA_A and test side HDMI_HPD, signal end HPA_A is coupled to control unit 110, test side HDMI_HPD is in order to be coupled to source equipment 30, and be coupled with voltage regulation resistance R between signal end HDMI_HPD and test side HPA_A, in order to electrostatic defending effect to be provided, and the specification of serial clock wire pin 112 and serial data wire pin 113 meets the standard of I2C, in order to the signal communicating path as between source equipment 30 and terminal equipment 20, generally in terminal equipment 20, be provided with an internal memory, in order to deposit the expanded display recognition data (Extended Display Identification Data, EDID) of the resolution (resolution such as 720P or 1080P) that terminal equipment 20 supports.Source equipment 30 be coupled to the internal memory of terminal equipment 20 by serial clock wire pin 112 and serial data wire pin 113, expanded display recognition data (EDID) in order to reading terminal equipment 20, and corresponding transition minimized differential signaling (the Transition-Minimized Differential Signaling that meets HDMI specification that sends, TMDS), to terminal equipment, terminal equipment is obtained meet the image frame of its resolution.

Power module 120 is respectively coupled to HDMI interface 110 and control unit 130, wherein between power module 120 and HDMI interface 110, is also coupled with a plurality of resistance, and power module 120 is coupled to hot plug detecting pin 111 by the first resistance R 1 in a plurality of resistance; By the second resistance R 2, be coupled to serial clock wire pin 112; And be coupled to serial data wire pin 113 by the 3rd resistance R 3, wherein the first resistance R 1, the second resistance R 2 and the 3rd resistance R 3 are respectively pull-up resistor, allow hot plug detecting pin 111, serial clock wire pin 112 and serial data wire pin 113 in the situation that having power supply supply, maintain high level, make control unit 130 correspondingly send hot plug detection signal, and avoid serial clock wire pin 112 and serial data wire pin 113 to produce logic error on follow-up signal handling procedure.Power module 120 is in order to provide the power supply PWR1 of terminal equipment to serial clock wire pin 112 and serial data wire pin 113, and the level of the Signal Regulation hot plug transmitting according to control unit 130 detecting pin 111 changes, for example output voltage, to hot plug detecting pin 111, makes it from low level state, be converted to high level state.

Control unit 130 is respectively coupled to HDMI interface 110 and power module 120.Control unit 130 can be but be not limited to central processing unit (Central Processing Unit, CPU) or microcontroller (Micro-Controller Unit, MCU), in order to what receive HDMI interface 110, enable (enable) signal, and correspondence sends a control signal to power module 120, make power module 120 regulate the level of hot plug detecting pin 111 to change according to control signal; And change and send hot plug detection signal to source equipment 30 in order to corresponding level, thereby make source equipment 30 by the expanded display recognition data of serial clock wire pin and serial data wire pin reading terminal equipment.

Based on above-mentioned, interface on terminal equipment 20 is used state, while switching to HDMI interface 110 from other interfaces, can pass through control unit 130 detecting real-times to the enable signal of HDMI interface, and correspondence sends a control signal to power module 120, thereby make power module 120 detect pin 111 according to control signal power supply to the hot plug of HDMI interface 110 that provides initiatively, thereby trigger the hot plug detection signal of high level.Therefore, even if under the situation that the power pins on HDMI interface 110 or joint is damaged, source equipment 30 still can be detected the hot plug detection signal that pin receives high level by hot plug, and according to HDMI agreement, carry out the expanded display recognition data (EDID) of reading terminal equipment 20; And the corresponding transition minimized differential signaling (TMDS) that sends is to the program of terminal equipment 20, thereby terminal equipment 20 obtained and shown the image frame that meets its resolution.Therefore, in the present embodiment, HDMI interface 110 can be also other pins that only comprise outside power pins, and the configuration of omitting power pins, also can reach the effect of the hot plug detection signal that triggers high level, allow and can carry out according to HDMI agreement the program that reads expanded display recognition data (EDID) and send and receive transition minimized differential signaling (TMDS) of postorder between terminal equipment and source equipment, thereby allow terminal equipment 20 judge the existence of source equipment 30.

By an embodiment of the method, the realization of the application's method is described further below.As shown in Figure 4, the HDMI signal processing method flow chart for the application the first embodiment, comprising:

Step S110, receives the enable signal of HDMI interface by control unit;

Step S120, the corresponding enable signal of control unit sends a control signal to power module;

Step S130, power module regulates the level of the hot plug detecting pin of HDMI interface to change according to control signal;

Step S140, control unit changes according to level, the corresponding hot plug detection signal that sends; And

Step S150, hot plug detection signal is detected pin self terminal equipment by hot plug and is sent to source equipment.

Please refer to Fig. 1 to Fig. 4, interface on terminal equipment 20 is used state, from other signaling interfaces (such as VGA or DVI etc.), switch to HDMI interface 110, when HDMI interface 110 is enabled, HDMI signal processing circuit 10 receives the enable signal (step S110) of HDMI interface 110 by control unit 110.Then, the corresponding enable signal of control unit 110 sends a control signal to power module 120 (step S120), make the driven and corresponding control signal of power module 120 that the hot plug detecting pin 111 of power supply PWR1 to HDMI interface 110 is provided, making the signal end HDMI_HPD of hot plug detecting pin 111 is high level (step S130) from low transition.Then, the level that control unit 110 detects hot plug detecting pin 111 changes, and change the corresponding hot plug detection signal (step S140) that sends according to level, the test side HPA_A that makes hot plug detection signal detect pin 110 by hot plug is sent to source equipment 30, and completes the operation (step S150) that triggers hot plug signal.

Afterwards, between source equipment and terminal equipment, can carry out follow-up signal according to HDMI agreement and transmit flow process.As shown in Figure 1 and Figure 5, these follow-up signals transmission flow processs comprise:

Step S160, whether control unit detecting source equipment sends and minimizes transmission differential signal;

Step S170, if so, control unit judgement source equipment is coupled to terminal equipment by HDMI interface; And

Step S180, if not, control unit judgement source equipment is not coupled to terminal equipment.

Namely, by control unit 110, judge that source equipment 30 are after receiving hot plug detection signal, the expanded display recognition data (EDID) of reading terminal equipment 20 whether, and feed back corresponding transition minimized differential signaling (TMDS) and give terminal equipment 20, allow terminal equipment 20 confirm the connection status of itself and source equipment 30.Therefore, above-mentioned steps also comprises:

Step S161, source equipment receives hot plug detection signal, and by the serial clock wire pin of HDMI interface and the expanded display recognition data (EDID) of serial data wire pin reading terminal equipment;

Step S162, source equipment is according to expanded display recognition data (EDID), and corresponding transmission minimizes transmission differential signal (TMDS); And

Step S163, control unit receives and minimizes transmission differential signal (TMDS), and judgement source equipment is coupled to terminal equipment by HDMI interface.

So, terminal equipment 20 meets minimizing after transmission differential signal (TMDS) of HDMI standard in reception, the resolution playing video picture that can reach according to itself.

Please refer to Fig. 6 to Fig. 8, HDMI signal processing circuit 10 and the first embodiment that the application the second embodiment discloses are roughly the same, difference is between the two, HDMI interface 110 also comprises power pins 114, and power pins 114 is coupled to hot plug detecting pin 111 by the first resistance R 1 equally; The second resistance R 2 is coupled to serial clock wire pin 112; And the 3rd resistance R 3 be coupled to serial data wire pin 113, in order to the power supply PWR2 provide from source equipment to be provided, and power supply PWR2 is sent to serial clock wire pin 112 and serial data wire pin 113; And be sent to hot plug detecting pin 111 and triggering hot plug detection signal.

In addition,, for the configuration in response to power pins 114, between power module 120 and the first resistance R 1, be also electrically provided with the first diode D1; And be also electrically provided with the second diode D2 between power pins 114 and the first resistance R 2, the first diode D1 and the second diode D2 regulate respectively power module 120 and the power supply of power pins 111 to be supplied to hot plug detecting pin 111, and what the power supply PWR1 that makes to come from power module 120 and the power supply PWR2 that comes from power pins 111 can be average powers to the load.Similarly, between power module 120 and serial clock wire pin 112 and serial data wire pin 113, be electrically provided with the 3rd diode D3; And be electrically provided with the 4th diode D4 between power pins 114 and serial clock wire pin 112 and serial data wire pin 113, wherein the 3rd diode D3 and described the 4th diode D4 are coupled to serial clock wire pin 112 and are coupled to serial data wire pin 113 by the 3rd resistance R 3 by the second resistance R 2, in order to regulate power module 120 and the power supply of power pins 111 to be supplied to serial clock wire pin 112 and serial data wire pin 113.

Therefore, in the present embodiment, hot plug detection signal can be to be triggered or initiatively triggered by terminal equipment 20 by source equipment 30.That is to say, when the signaling interface of terminal equipment 30 is switched to HDMI interface 110 from other interfaces, whether the level that control unit 130 can first be detected hot plug detecting pin 111 changes; If so, the function of power pins 114 that represents HDMI interface 110 (or joint) is normal, and transmits power supplys to hot plugs detecting pin 111 from source equipment 30, thereby triggers hot plug detection signal, to complete follow-up signal convey program; If not, control unit 130 judges power pins 114 damages of HDMI interface 110 (or joint), and send a control signal to power module 120, and initiatively trigger hot plug detection signal by terminal equipment, so that complete follow-up signal convey program.So, can guarantee that no matter terminal equipment 20 is under the good or situation damaged of power pins 114 on HDMI interface 110 (or joint), all can complete smoothly the trigger of heat plug signal, thereby make the expanded display recognition data (EDID) that source equipment can reading terminal equipment, and terminal equipment can be received minimize transmission differential signal (TMDS) to carry out playing video picture.

With certain methods embodiment, the realization of the application's the second embodiment HDMI signal processing circuit is described further below.What deserves to be explained is, disclosed the second embodiment of the application also can realize by the processing method identical with the first embodiment the program that triggers hot plug signal, because its step is identical or close, does not repeat them here.Other implementations for the application HDMI signal processing method are described further below.

As shown in Figure 9, the HDMI signal processing method flow chart for the application the second embodiment, comprising:

Step S210, receives the enable signal of HDMI interface by control unit;

Step S220, control unit is detected pin by hot plug and is initiatively sent hot plug detection signal to source equipment; And

Step S230, whether control unit detecting source equipment sends and minimizes transmission differential signal;

Step S231, if so, control unit judgement source equipment is coupled to terminal equipment by HDMI interface;

Step S232, if not, control unit continues to send hot plug detection signal to source equipment, and waits for that source equipment feedback minimizes transmission differential signal; And if control unit do not detect and minimize transmission differential signal within the scheduled time, control unit is carried out the operation transmitting control signal.

Step S240, the corresponding enable signal of control unit sends a control signal to power module;

Step S250, power module regulates the level of the hot plug detecting pin of HDMI interface to change according to control signal;

Step S260, control unit changes according to level, the corresponding hot plug detection signal that sends; And

Step S270, hot plug detection signal is detected pin self terminal equipment by hot plug and is sent to source equipment.

Please refer to Fig. 6 to Fig. 9, in the disclosed HDMI signal processing method of the application the second embodiment, interface on terminal equipment 20 is used state, from other signaling interfaces, switch to HDMI interface 110, when HDMI interface 110 is enabled, HDMI signal processing circuit 10 receives the enable signal (step S210) of HDMI interface 110 by control unit 130.Then, control unit 130 first initiatively sends hot plug detection signal to source equipment 30 by the hot plug detecting pin 111 of HDMI interface 110, to confirm the connection status (step S220) of source equipment.

Then, whether control unit 110 detecting source equipment 30 send and minimize transmission differential signal (TMDS) (step S230), if, represent that source equipment 30 has received hot plug detection signal, and completed the fetch program of the expanded display recognition data (EDID) of terminal equipment 20, thereby allowed control unit 130 judgement source equipment 30 by HDMI interface 110, be coupled to terminal equipment 20 (step S231); If not, control unit 130 first judges that source equipment 30 may be subject to some factor and disturb, and fail real-time to set up HDMI communication protocol with terminal equipment 20, therefore, control unit 130 continues to send hot plug detection signal to source equipment 30, for example with interval, be greater than the frequency of 3 seconds to 30 inquiries of source equipment, and wait for that source equipment 30 feedbacks minimize transmission differential signal (TMDS); If source equipment 30 feeds back transition minimized differential signaling (TMDS) in the given time, control unit 130 judges that the HDMI communication protocol between source equipment 30 and terminal equipment 20 sets up.

Otherwise, if detecting within the scheduled time, control unit 130 do not minimize transmission differential signal (TMDS), control unit 130 judges that source equipment 30 not yet connects or the power pin of HDMI interface 110 (or joint) 114 damages, thereby carries out the operation (step S232) transmitting control signal.Namely the enable signal by the corresponding HDMI interface 110 of control unit 130 sends a control signal to power module 120, by power module 120, regulate the level of the hot plug detecting pin of HDMI interface 110 to change, thereby make terminal equipment 20 initiatively trigger hot plug detection signal, and by hot plug, detect pin 111 hot plug detection signal is sent to source equipment 30, so that reaffirm the annexation between source equipment 30 and terminal equipment.If source equipment 30 is coupled to terminal equipment 20 in open state, source equipment 30 is the expanded display recognition data (EDID) that corresponding hot plug detection signal is carried out reading terminal equipment 20, and transmit corresponding transition minimized differential signaling (TMDS) to terminal equipment 20, thereby allow the HDMI communication protocol between control unit judgement source equipment 30 and terminal equipment 20 set up.

In addition, in the present embodiment, because the hot plug detecting pin of HDMI interface also can provide power supply by source equipment, therefore, at control unit 130, initiatively send hot plug detection signal to before the operation of source equipment 30, under can also comprising with step:

Step S200, the level that control unit is detected hot plug detecting pin within the scheduled time changes;

Step S201, if hot plug detecting pin is high level by low transition, control unit judgement source equipment is coupled to terminal equipment by HDMI interface, the corresponding hot plug detection signal that sends of control unit is to source equipment; And

Step S202, if the level of hot plug detecting pin is unchanged, control unit is carried out and is initiatively sent hot plug detection signal to the operation of source equipment.

Please refer to Fig. 6 to Figure 10, that is to say, when control unit 130 receives enable signal from HDMI interface 110, the level that control unit 130 is first detected the hot plug detecting pin 111 of HDMI interface 110 changes, if hot plug detecting pin 111 is high level from low transition, control unit 130 judges that the power pins 114 of HDMI interface 110 is normal power supply state, and the corresponding hot plug detection signal that sends is to source equipment 30, also just can omit the down-stream that changes the level state of hot plug detecting pin 111 by power module 120.Otherwise, if detecting the level of hot plug detecting pin 111, control unit 130 do not change, control unit judges that the power pins 114 of HDMI interface 110 (or joint) may damage, thereby initiatively trigger hot plug detection signal by power module 120, so that set up the HDMI communication protocol between terminal equipment 20 and source equipment 30.

Above-mentioned explanation has illustrated and has described some preferred embodiments of the application, but as previously mentioned, be to be understood that the application is not limited to disclosed form herein, should not regard the eliminating to other embodiment as, and can be used for various other combinations, modification and environment, and can, in invention contemplated scope described herein, by technology or the knowledge of above-mentioned instruction or association area, change.And the spirit and scope that the change that those skilled in the art carry out and variation do not depart from the application, all should be in the protection range of the application's claims.

Claims

1. a HDMI signal processing circuit, is applicable on terminal equipment, and described terminal equipment is coupled to source equipment by described HDMI signal processing circuit, and described terminal equipment comprises control unit, it is characterized in that, described HDMI signal processing circuit comprises:

HDMI interface, is coupled to described control unit, and described HDMI interface comprises hot plug detecting pin, serial clock wire pin and serial data wire pin; And

Power module, is respectively coupled to described HDMI interface and described control unit;

Wherein, described control unit receives the enable signal of described HDMI interface, and correspondence sends a control signal to described power module, described power module regulates the level of described hot plug detecting pin to change according to described control signal, the corresponding described level of described control unit changes by described hot plug detects pin transmission hot plug detection signal to described source equipment, makes described source equipment by described serial clock wire pin and described serial data wire pin, read the expanded display recognition data of described terminal equipment.

2. HDMI signal processing circuit as claimed in claim 1, is characterized in that, also comprises:

The first diode, the second diode and a plurality of resistance, and described HDMI interface also comprises power pins, wherein said a plurality of resistance comprises the first resistance, the second resistance and the 3rd resistance, described power module is coupled to described hot plug detecting pin by described the first resistance, by described the second resistance, be coupled to described serial clock wire pin and be coupled to described serial data wire pin by described the 3rd resistance, described the first diode is coupled between described the first resistance and described power module, described the second diode is coupled between described the first resistance and described power pins, described the first diode and described the second diode are in order to regulate described power module and described power pins supply power supply to described hot plug detecting pin.

3. HDMI signal processing circuit as claimed in claim 2, is characterized in that, also comprises:

The 3rd diode and the 4th diode, described the 3rd diode is coupled to described power module, described the 4th diode is coupled to described power pins, and described the 3rd diode and described the 4th diode are coupled to described serial clock wire pin and are coupled to described serial data wire pin by described the 3rd resistance by described the second resistance.