[summary of the invention]
Fundamental purpose of the present invention is: provide a kind of ability simple quick identification external equipment plug, the power supply interface device and the electric supply interface method of the external equipment of instant conducting or power cutoff.
For realizing above-mentioned purpose, the present invention proposes a kind of power supply interface device of external equipment, comprises reference level supervisory circuit, working power switch, signaling interface socket, working power interface socket; Said signaling interface socket comprises first signal pins, this first signal pins and the coupling of said reference level supervisory circuit input end; Said working power switch control end is connected with said reference level supervisory circuit output terminal; Said working power switch input terminal is used to connect working power, and output terminal is connected with said working power interface socket; When said reference level supervisory circuit monitors the said first signal pins generation level saltus step, the output control signal, the break-make of Control work power switch is for the working power interface socket powers on or cuts off the power supply.
Above-mentioned power supply interface device also comprises the signal monitoring power supply, is connected with said reference level supervisory circuit, working power switch, signaling interface socket respectively.
Above-mentioned power supply interface device, said signaling interface socket also comprises positive source pin, power cathode pin; Said positive source pin, power cathode pin and the coupling of said signal monitoring power supply.The length of said first signal pins slightly is shorter than the length of said positive source pin, power cathode pin.
Above-mentioned power supply interface device, said signaling interface socket also comprises the secondary signal pin, itself and said first signal pins, positive source pin, power cathode pin constitute a standard USB interface socket.Said reference level supervisory circuit comprises the USB controller, and said working power switch, signaling interface socket are electrically connected with it respectively.Said signaling interface socket, supply socket are integrated, and are combined into the signal power source multi-cable socket.
Above-mentioned power supply interface device, said signaling interface socket also comprises the secondary signal pin, itself and said first signal pins are coupled with said signal monitoring power supply respectively.
Above-mentioned power supply interface device; Said reference level supervisory circuit comprises comparator circuit; Said comparator circuit one input end is used to connect reference voltage; First signal pins of another input end and said signaling interface socket or the coupling of secondary signal pin, said comparator circuit output terminal is connected with said working power switch control end.Also comprise subtraction circuit, isolated drive circuit, said subtraction circuit one end is electrically connected with said signaling interface socket, and the other end is electrically connected with said isolated drive circuit.
Simultaneously; The present invention proposes a kind of electric supply interface method of external equipment; Utilize the level of the signal path that the monitoring in real time of above-mentioned power supply interface device is used for joining with external equipment to change, change according to this level, for external equipment connects working power or breaks off working power.
Above-mentioned electric supply interface method is drawn simultaneously by the signaling interface of power supply interface device and to be connect the signal monitoring power supply; When external equipment inserted or extracts the signaling interface of interface electric supply installation, the level that the power supply interface device detects on the signal path in advance changed, and provides the control signal of working power switch again, for the power supply interface of power supply interface device powers on or cuts off the power supply.
Above-mentioned electric supply interface method, said signaling interface, power supply interface are combined into a compound interface, and signal pins wherein is made as and slightly is shorter than signal monitoring power pins and working power pin; When making external equipment extract the compound interface of interface electric supply installation, the connection of signal pins is at first broken off, and the level that produces on the signal path is jumped down.
Above-mentioned electric supply interface method is when external equipment breaks away from being connected of power supply interface device, before power supply interface disengages; Signal path disengages in advance; The level that the power supply interface device detects on the signal path changes, and provides the control signal of power switch, is the power supply interface outage.
Above-mentioned electric supply interface method, when external equipment was connected with the power supply interface device, the level on the signal path changed, and the power supply interface device detects this level to be changed, and provides the control signal of working power switch, for power supply interface powers on.
Owing to adopted above scheme; Through detecting the saltus step of interface signal level; Realized the insertion of external working equipment and extracted identification, and conducting or turn-off the working power switch thus, for the power supply interface device powers on or cuts off the power supply; Realized the hot plug of the external equipment of external power supply, avoided since socket directly power supply and under big current conditions, strike sparks, the arcing phenomenon.Increased equipment life on the one hand; In addition on the one hand, increase the reliability of equipment operation, more met the Medical Devices safety requirements.
Scheme of the present invention, just power supply is safe and reliable behind the external equipment grafting power supply interface device; When external equipment was extracted, before socket broke away from fully, working power is reliable turn-off, had stopped to strike sparks and the arcing phenomenon when working power interface breaks away from; After external equipment was extracted, interface was not charged, and for contacting but live part does not more satisfy security needs.
The present invention can directly adopt usb circuit on circuit is realized, in the plug moment of external working equipment, and mouthful detection of signal level saltus step that achieves a butt joint, conducting or shutoff working power switch thus; And under working equipment works on power state, can utilize its signalling channel again as the data communication channel between external working equipment and the host computer; Device of the present invention is efficiently utilized, save resource and cost greatly.
Circuit of the present invention is realized also can adopting discrete device, and circuit is realized simple, and is with low cost, reliable.
Scheme of the present invention, power supply interface device can be external device one tunnel working power and one road low-power dissipation power supply are provided, and are specially adapted to power supply is had the external equipment of big current requirements.
[embodiment]
Below through concrete embodiment and combine accompanying drawing that the present invention is described in further detail.
Embodiment one:
Fig. 1 is circuit theory diagrams of the present invention; Power supply interface device of the present invention comprises reference level supervisory circuit, working power switch, signaling interface socket, supply socket, 5V signal monitoring power supply, and the signaling interface socket comprises first signal pins, positive source pin, power cathode pin; Positive source pin, power cathode pin are used to connect the signal monitoring power supply, first signal pins and the coupling of reference level supervisory circuit input end; Working power switch control end is connected with reference level supervisory circuit output terminal; The working power switch input terminal is used to connect working power, and output terminal is connected with supply socket; When the reference level supervisory circuit monitors the first signal pins generation level saltus step, the output control signal, the break-make of control switching is for supply socket powers on or cuts off the power supply.
Fig. 2, Fig. 3 are a kind of physical circuit way of realization of this programme power supply interface device, are applicable to the external equipment that possesses USB interface.In the circuit, the reference level supervisory circuit directly adopts the USB controller, and J1 is a two-in-one signal power source multi-cable socket, is combined as a whole by signaling interface socket and working power interface socket and forms.The signaling interface socket is pin PIN1~PIN4 pin; Adopt the USB_A type socket of a standard; The first signal pins PIN2 and secondary signal pin PIN3 are device signal line (differential lines to) socket; Positive source pin PIN1, power cathode pin PIN4 are the signal monitoring power pins, draw to connect+the signal monitoring power supply of 5V; Pin PIN6, PIN7 pin are the socket of working power interface socket, are used to draw connect+the 12V working power.U1 is a USB controller.The USB standard criterion is deferred in the PIN1 of USB controller U1 and JI~PIN4 design.Differential signal on PIN2 and the PIN3 is drop-down through the first pull down resistor R44, the second pull down resistor R45.U4 is an esd protection circuit, plays electrostatic protective function, and U3 is the switch mosfet pipe, is the pin one power supply of J1.
This example directly utilizes the inner MCU that embeds of USB controller U1 to carry out the differential signal line level judging.PIN1~PIN4 of USB controller U1, switch mosfet pipe U3, esd protection circuit U4, the first pull down resistor R44, the second pull down resistor R45 and signal power source multi-cable socket JI has constituted a complete power supply interface device.
When switch mosfet pipe U3 does not enable, be in high-impedance state, output 5V voltage, but electric current is less than 100mA.Add human body resistance 1K, the maximum 5mA electric current that produces, such voltage can not cause shock hazard to human body.So at medical instruments field, it belongs to " not charged " parts.Therefore, in the scheme of the present invention, when external equipment did not insert, the power supply interface device did not just have the power supply of 12V, and promptly it still is " not charged " state, can not cause danger to human body.After enabling, be in low resistive state, exportable 5V voltage, maximum current 500mA.Pin PIN1 is to be connected 5V signal monitoring power supply with PIN4 always, is used for detecting power supply.
External equipment adopts an interface socket two-in-one, that mate fully with signal power source multi-cable socket J1.Carry out the signal transmission with host computer through USB, meet the USB standard in the design equally.External equipment needs+12V and+5V two-way power supply, wherein ,+12V power supply has the work requirements of 5A.
This routine workflow is as shown in Figure 4.The power supply interface device provides the signal monitoring power supply and signal path is provided for external equipment simultaneously.On signal wire, the power supply interface device is drop-down, draws on the external equipment.Its course of work does, when external equipment inserts or extracts, the level on the signal wire will change, and the power supply interface device detects this variation, provides the control signal of working power switch, for the power supply interface device provides working power or outage.
As shown in Figure 5.When external unit inserted, the long and short hands structure of socket made PIN1, PIN2 connect prior to signal PIN2, PIN3, and external unit is the signal monitoring power supply of acquisition+5V earlier.Owing to draw on the DM of external unit or the DP signal, after PIN2, PIN3 connected, DM or DP signal voltage benchmark changed.The inner embedded MCU of USB controller U1 will detect the variation (DM or DP signal voltage benchmark change) of differential signal level, and USB controller U1 pin PSW1 provides low level.Triode Q1 conducting, optocoupler U2 work, make optocoupler U2 3,4 pin conductings and become low level, switch mosfet pipe Q2 conducting ,+12V working power is that PIN6, the PIN7 pin of the working power interface socket of signal power source multi-cable socket J1 powers on.Like this, the external equipment operate as normal required+the 12V power supply electrifying.
When external equipment was extracted, because PIN1~PIN4 is the USB_A type socket of a standard, its special length contact pin design made PIN2, PIN3 at first break off.When plug was not extracted fully, the level saltus step had appearred in signal wire.The inner embedded MCU of USB controller U1 will detect the variation of differential signal level; USB controller U1 pin PSW1 provides high level; Triode Q1 turn-offs, and light idol U2 does not work, and makes the pin 4 of optocoupler U2 become high level; Switch mosfet pipe Q2 by, on the PIN6 of signal power source multi-cable socket J1, the PIN7 pin+12V outage.Because the processing time is extremely short, when the plug of external equipment is not also extracted fully, on the power supply interface device+the 12V power supply is cut off.Sparking, arcing phenomenon under the big current conditions have been stopped.It is not charged simultaneously to have guaranteed that equipment is extracted rear port yet, more satisfies the Medical Devices security needs.
In this programme, the power supply interface circuit is that external equipment provides+12V and+5V power supply.Be specially adapted to external device right+12V has the application of big current requirements (maximum continuous current 5A).
Embodiment two:
This routine principle of work is identical with embodiment one; Difference is; Its circuit adopts discrete device as shown in Figure 6 to realize, comprise comparer, signal power source multi-cable socket, working power switch, subtracter, isolation and driving circuit, comparer is as the reference level supervisory circuit; In the signal power source multi-cable socket in second pin, the 3rd pin any pin be connected to comparer "+" end; Comparer "-" termination 4V voltage, comparator output terminal is connected to the control of power switch and extremely goes up, with control+12V break-make.When external equipment inserted, second pin, the 3rd pin reference level saltus step were 5V, greater than 4V voltage, made comparer export high level, and power switch is connected, and is external equipment confession+12V.Second pin, the 3rd pin are multiplexed with the usefulness of signal wire as data transmission simultaneously, deduct the 5V reference level through subtraction circuit after, through isolating and driving circuit, deliver to host computer.
In this routine discrete device implementation, first pin to the, four pins are similarly the length contact pin design of similar USB_A type socket, and first pin, the 4th pin maintenance+5V often supply power.Make when inserting, the contact earlier of first pin, the 4th pin, external device has the 5V power supply earlier; Second pin when extracting, the 3rd pin break off earlier, and second pin, the 3rd pin reference level are at first fallen and be 0V; After comparer detects the level saltus step, the output high level, power switch is connected, and is external equipment confession+12V.
Embodiment three:
This routine principle of work is identical with embodiment one, and difference is, and is as shown in Figure 7; Omitted partial circuit, and socket J1 changes the 6PIN socket into its concrete realization in the circuit; PIN1 wherein and PIN2 be through drawing on the first pull-up resistor R46, the second pull-up resistor R47, the signal monitoring power supply of connection+5V, and that the corresponding pin of external equipment carries out is drop-down; When external equipment inserts; Signal generation saltus step on PIN1 and the PIN2, the inner embedded MCU of USB controller U1 will detect the variation (DM or DP signal voltage benchmark change) of differential signal level, and USB controller U1 pin PSW1 provides low level.Triode Q1 conducting, optocoupler U2 work, make optocoupler U2 3,4 pin conductings and become low level, switch mosfet pipe Q2 conducting ,+12V working power is that PIN4, the PIN5 pin of the working power interface socket of signal power source multi-cable socket J1 powers on.Like this, the external equipment operate as normal required+the 12V power supply electrifying.
Method of the present invention and device thereof in our company's type multiparameter patient monitor performance history, being applied, and are realized in the exploitation model machine.Actual verification is feasible, reliable, has realized the goal of the invention of expection.
Above content is to combine concrete preferred implementation to the further explain that the present invention did, and can not assert that practical implementation of the present invention is confined to these explanations.For the those of ordinary skill of technical field under the present invention, under the prerequisite that does not break away from the present invention's design, can also make some simple deduction or replace, all should be regarded as belonging to protection scope of the present invention.Such as, the long and short hands design of pin can realize in the interface socket of external equipment, and power supply interface circuit of the present invention does not need the long and short hands design; The concrete implementation of power supply interface circuit is also varied.