CN201536253U - USB overcurrent detection and control circuit - Google Patents
USB overcurrent detection and control circuit Download PDFInfo
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- CN201536253U CN201536253U CN2009202049036U CN200920204903U CN201536253U CN 201536253 U CN201536253 U CN 201536253U CN 2009202049036 U CN2009202049036 U CN 2009202049036U CN 200920204903 U CN200920204903 U CN 200920204903U CN 201536253 U CN201536253 U CN 201536253U
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Abstract
The utility model discloses a USB overcurrent detection and control circuit, which comprises a sampling module, an amplifying module, a comparing module, and a CPU, wherein the sampling module samples current signals in a plurality of USB main circuits and converts the current signals to voltage signals; the amplifying module amplifies the voltage signals; the comparing module compares the voltage signals and generates level signals to indicating the real-time current states; the CPU receives the level signals, and then selectively controls switch control modules on a plurality of USB branch circuits after detecting that the current exceeds the set value; and the sampling module, the amplifying module, and the comparing module are connected in series sequentially, and the comparing module is further connected with the CPU. The utility model can selectively process all the USB power supply circuits, and realizes the overcurrent detection and control, so as to ensure the normal work of the product.
Description
Technical field
The utility model relates to electronic technology, relates in particular to detection and the resist technology of USB.
Background technology
A large amount of devices about USB over-current detection and protection class are arranged in the market, for example following several.
1, overcurrent protection in case the outlet overcurrent condition is just cut off the electricity supply, recovers after overcurrent condition disappears;
2, over-current detection pin occurs detecting behind the overcurrent condition and sends over-current signal, overcurrent condition is not handled;
3, over-current detection and protection are just cut off the electricity supply in case overcurrent condition occurs, detect pin simultaneously and send over-current signal, recover after overcurrent condition disappears;
For example; at the disclosed Chinese patent that patent publication No. is CN201149942 of Patent Office of the People's Republic of China; its open day is 2008.11.12; it discloses the USB switching device that a kind of current margin optionally has overcurrent protection function; be that the USB switching device is provided with a plurality of insurances that recover certainly; can make things convenient for the user that current range is selected, and, automatically USB device be finished overcurrent protection by from the characteristic of recovering insurance.Technical scheme is: comprise interconnective first usb interface module and second usb interface module, described first USB interface is used for being connected with USB device, described second USB interface is used for being connected with the upstream USB interface, also be provided with and be used to limit size of current and the electric current that current margin is selected is limited and select module, described electric current restriction and select module to be connected on the Vbus holding wire or GND holding wire between first usb interface module and second usb interface module, the D+ holding wire of described first usb interface module and D-holding wire link to each other with the D+ holding wire and the D-holding wire of described second usb interface module respectively.
But, more existing electronic equipments, family multi-media equipment for example, office equipment or the like, the capital is equipped with one or more USB interface, and the electronic equipment of description of the Prior Art all is the indiscriminate branch road to overcurrent in back to occur at overcurrent condition to turn-off processing, and single channel USB power supply circuits electric current is normal when occurring, and overall current exceeds the situation of requirement, then can't selectively handle each USB power supply circuits.
Therefore, along with popularizing and development of USB technology, single channel USB power supply circuits electric current to occur normal when electronic equipment, and overall current exceeds the situation of requirement, how selectively each USB power supply circuits to be handled, make the product operate as normal, become problem anxious to be solved.
The utility model content
The purpose of this utility model provides a kind of USB over-current detection and control circuit, single channel USB power supply circuits electric current to occur normal when electronic equipment, and overall current exceeds the situation of requirement, can selectively handle each USB power supply circuits, realize over-current detection and control, make the product operate as normal.
For solving the problems of the technologies described above, the utility model discloses a kind of USB over-current detection and control circuit, wherein, comprising:
Current signal in a plurality of USB main line is sampled and current signal is converted to the sampling module of voltage signal;
Carry out the amplification module that described voltage signal amplifies;
The comparison module that described voltage signal is compared; With
Receive the more described voltage signal of described comparison module and produce after the level signal of expression real-time current state and detect electric current and the CPU that selects the switch control module on a plurality of USB branch roads of control is arranged after exceeding set point; Wherein,
Sampling module, amplification module and comparison module are connected successively, and comparison module also connects described CPU.
More excellent, described sampling module further comprises first resistance and second resistance of two parallel connections, wherein, and the circuit after the described parallel connection, one end connects 5V supply network and described amplification module, and the other end connects laod network and the described amplification module of two-way or multichannel USB.
More excellent, described amplification module further comprises: first amplifier, the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance, wherein, the negative input of described first amplifier is connected with laod network by described the 3rd resistance and forms feedback circuit by described the 5th resistance and its output, and the electrode input end of described first amplifier is connected with supply network by described the 4th resistance and passes through described the 6th grounding through resistance.
More excellent, described comparison module further comprises: second amplifier, the 7th resistance, the 8th resistance, the 9th resistance and voltage-stabiliser tube, wherein, the electrode input end of described second amplifier is connected with the output of described first amplifier by described the 7th resistance, the negative input of described second amplifier is connected with reference voltage by described the 8th resistance, the output of described second amplifier connects the universal input/output interface GPIO_IN of CPU by the 9th resistance, and connects described voltage-stabiliser tube between the universal input/output interface GPIO_IN of described the 9th resistance and described CPU.
More excellent, described switch control module further comprises: NPN pipe, the tenth resistance, the 11 resistance, the 16 resistance, the 17 resistance, the 18 resistance, the 19 resistance, electric capacity and P channel MOS tube Q9, wherein, one end of described the 17 resistance connects the universal input/output interface GPIO_IN of described CPU,, the other end connects the base stage of described NPN pipe, wherein, the two ends of described the 18 resistance connect the base stage and the emitter of described NPN pipe respectively
The collector electrode of described NPN pipe connects an end of described the tenth resistance and an end of described the 16 resistance, the other end of described the 16 resistance is connected with the grid of described P channel MOS tube Q9 by described the 11 resistance, and the other end of described the 16 resistance is also simultaneously by described the 19 resistance, and described electric capacity connects with the source class of described P channel MOS tube Q9;
The other end of described the tenth resistance all is connected with described laod network with the source class of described P channel MOS tube Q9, and the drain electrode of described P channel MOS tube Q9 connects described external USB device port USB_PORT1.
Compared with prior art, the utlity model has following beneficial effect:
The utility model discloses a kind of USB over-current detection and control circuit, utilize switch control module, when detecting electric current, CPU just can selectively control switch on the branch road of different USB after exceeding set point, thereby realize operating state main line current detecting, the function that the branch road power supply is selectively turn-offed.Therefore, single channel USB power supply circuits electric current to occur normal when electronic equipment, and overall current exceeds the situation of requirement, can selectively each USB power supply circuits be handled, and realizes over-current detection and control making the product operate as normal.
Description of drawings
Fig. 1 is a kind of USB over-current detection of the utility model preferred embodiment and the structural representation of control circuit;
Fig. 2 is the USB over-current detection of the utility model preferred embodiment and the switch control module electrical block diagram in the control circuit.
Embodiment
The utility model discloses a kind of USB over-current detection and control circuit, and single channel USB power supply circuits electric current to occur normal when electronic equipment, and overall current exceeds the situation of requirement, can selectively each USB power supply circuits be handled, and makes the product operate as normal.
As described in Figure 1, be a kind of USB over-current detection of the utility model preferred embodiment and the structural representation of control circuit.This USB over-current detection and control circuit can comprise: sampling module 11, and amplification module 12 and comparison module 13, wherein, and sampling module 11, amplification module 12 is connected successively with comparison module 13.
Wherein, sampling module 11 further comprises first resistance R 1 and second resistance R 2 of two parallel connections.Described amplification module 12 may further include: the first amplifier U1-A and four resistance: the 3rd resistance R 3, the four resistance R, 4, the five resistance R 5 and the 6th resistance R 6.Described comparison module 13 further comprises: the second amplifier U1-B, three resistance: the 7th resistance R 7, the eight resistance R 8 and the 9th resistance R 9, and voltage-stabiliser tube Z1.Circuit connecting relation can as figure and following as described in.
As shown in Figure 1, the circuit after described first resistance R 1 and 2 parallel connections of second resistance R, an end connects 5V supply network and described amplification module 12, and the other end connects laod network and the described amplification module 12 of two-way or multichannel USB.Current signal in a plurality of USB of the sampling module 11 samplings main line, and utilize the resistance in it to convert current signal to voltage signal, sampling module 11 exports this voltage signal to described amplification module 12, exporting to a comparison module 13 then by the amplification of amplification module 12 compares, comparison module 13 is relatively represented real-time current status to level signal of CPU (not shown) output after this voltage signal, when detecting electric current, CPU just can selectively control switch control module on USB1 or the USB2 branch road after exceeding set point, thereby realize operating state main line current detecting, the function that the branch road power supply is selectively turn-offed.
The concrete course of work can be elaborated by Fig. 1 and Fig. 2, and is as described below.
The effect of described sampling module 11 is that the current signal on the supply network is converted to voltage signal, and its structure and the course of work can be as follows.
5V is the supply network of two-way or multichannel USB, and USB_LOAD1 and USB_LOAD2 are laod network, and first resistance R 1 and second resistance R 2 are sample resistance.When non-loaded access USB_LOAD1, there is not electric current to flow through above the 5V network, first resistance R 1 and second resistance R, 2 two ends do not have pressure drop, i.e. 5V-USB_LOAD1=0V.
When inserting, have electric current I to flow through on the 5V network when USB_LOAD1 or USB_LOAD2 network have load (promptly having USB device to insert), this moment, first resistance R 1 and second resistance R, 2 two ends can produce pressure drop, i.e. 5V-USB_LOAD1=I* (R1//R2).
The voltage signal of sampling module 11 outputs amplifies sampled signal through amplification module 12, makes comparisons through comparison module 13 and reference voltage again, afterwards comparative result is exported to universal input/output interface GPIO_IN, specifically can be as described below.
In the amplification module 12, the negative input of the described first amplifier U1-A is connected with laod network by described the 3rd resistance R 3 and the output pin by described the 5th resistance R 5 and the first amplifier U1-A 1 forms feedback circuit, and the electrode input end of the described first amplifier U1-A is connected with supply network by described the 4th resistance R 4 and by described the 6th resistance R 6 ground connection.
In the comparison module 13, the electrode input end of the described second amplifier U1-B is connected with the output of the described first amplifier U1-A by described the 7th resistance R 7, the negative input of the described second amplifier U1-B is connected with reference voltage by described the 8th resistance R 8, the output of the described second amplifier U1-B connects described voltage-stabiliser tube Z1 by the universal input/output interface GPIO_IN of the 9th resistance R 9 connection CPU between the universal input/output interface GPIO_IN of described the 9th resistance R 9 and described CPU.
In the amplification module 12, the 3rd resistance R 3 equates that with the resistance of the 5th resistance R 5 the 4th resistance R 4 equates with the resistance of the 6th resistance R 6, can adjust the multiplication factor of the first amplifier U1-A by the resistance of regulating these four resistance.When USB_LOAD1 and the non-loaded access of USB_LOAD2 network, during 5V-USB_LOAD1=0V, the first amplifier U1-A difference input voltage equates that difference is 0V, and after this difference was amplified, the first amplifier U1-A pin 1 was output as 0V.VREF is a reference voltage (gets on the occasion of), the signal of the first amplifier U1-A pin, 1 output is transferred to the second amplifier U1-B, after utilizing reference voltage V REF to compare, the second amplifier U1-B exports the universal input/output interface GPIO_IN of CPU to, this moment, less than VREF, then the universal input/output interface GPIO_IN of CPU was a low level because of U4-A the 1st pin voltage.
When USB_LOAD1 and USB_LOAD2 network have load to insert, load current is I, the first amplifier U1-A difference input voltage is: 5V-USB_LOAD1=I* (R1//R2), this voltage difference is exported by pin 1 after the first amplifier U1-A amplifies, the pin 1 of the first amplifier U1-A outputs voltage signal to the second amplifier U1-B, exports the universal input/output interface GPIO_IN of CPU after the second amplifier U1-B utilizes reference voltage V REF to compare to.When load current I surpasses set point, pin 1 output voltage of the first amplifier U1-A will be greater than reference voltage V REF, this moment, the universal input/output interface GPIO_IN of CPU exported high level, voltage-stabiliser tube Z1 can Controlled CPU the output voltage of universal input/output interface GPIO_IN, in order to avoid the too high GPIO mouth that burns out of output voltage.
System GPIO (universal input/output interface) comes the control switch control module according to the value that detects the universal input/output interface GPIO_IN of CPU, thereby realize flexible control to the two-way USB device, wherein, the electrical block diagram of switch control module as shown in Figure 2, the course of work of this switch control module can be as described below.
This switch control module can comprise: NPN manages Q10, the tenth resistance R 10, the 11 resistance R 11, the 16 resistance R 16, the 17 resistance R 17, the 18 resistance R 18, the 19 resistance R 19, capacitor C 78 and P channel MOS tube Q9.
Wherein, an end of the 17 resistance R 17 connects the universal input/output interface GPIO1 of CPU, and the other end connects the base stage B of NPN pipe Q10, and the signal that the universal input/output interface GPIO_IN of CPU detects is from base stage B input, from collector electrode C output, emitter E ground connection.Wherein, the two ends of the 18 resistance R 18 connect base stage B and the emitter E of NPN pipe Q10 respectively.
The collector electrode C of NPN pipe Q10 connects an end of the tenth resistance R 10 and an end of the 16 resistance R 16, the other end of the 16 resistance R 16 is connected with the grid (being the G utmost point) of P channel MOS tube Q9 by the 11 resistance R 11, and the other end of the 16 resistance R 16 also is connected with the source class (be the S utmost point) of capacitor C 78 with P channel MOS tube Q9 by the 19 resistance R 19 simultaneously.
The other end of the tenth resistance R 10 is connected with USB_LOAD1, and the source class of P channel MOS tube Q9 (being the S utmost point) all is connected with USB_LOAD1, and the drain electrode of P channel MOS tube Q9 (being the D utmost point) connects USB_PORT1.
The course of work of this switch control module can be as described below.
When the universal input/output interface GPIO_IN of CPU detects high level, can control GPIO1 and be output as high level, this moment, NPN pipe Q10 was in conducting state, the grid of P channel MOS tube Q9 (being the G utmost point) is dragged down, also be in conducting state, USB_LOAD1 voltage is delivered to USB_PORT1 by P channel MOS tube Q9, and USB_PORT1 is a USB device interface supply network.
When the universal input/output interface GPIO_IN of CPU detects high level, illustrate that the USB external loading has surpassed set point, be judged as over-current state, system's control this moment GPIO1 output low level, NPN pipe Q10 is in cut-off state, the grid of P channel MOS tube Q9 (being the G utmost point) is subjected to drawing on the R10 and is high level, and P channel MOS tube Q9 is turned off by the USB_PORT1 power supply, and USB device quits work.The universal input/output interface GPIO_IN that detects CPU up to system becomes low level once more, and the control GOIO1 of system recovers the power supply to USB device.
Can have two or more switch control modules in the system of electronic equipment, be subjected to the control of two or more GPIO simultaneously, so after the universal input/output interface GPIO_IN of CPU detects over-current signal, can control the power supply of wherein a road or multichannel USB device arbitrarily, thereby realize overall the detection, respectively the effect of Guan Duaning.
In sum, the utility model discloses a kind of USB over-current detection and control circuit, utilize switch control module, when detecting electric current, CPU just can selectively control switch on the branch road of different USB after exceeding set point, thereby realize operating state main line current detecting, the function that the branch road power supply is selectively turn-offed.Therefore, single channel USB power supply circuits electric current to occur normal when electronic equipment, and overall current exceeds the situation of requirement, can selectively each USB power supply circuits be handled, and realizes over-current detection and control making the product operate as normal.
Claims (5)
1. USB over-current detection and control circuit is characterized in that, comprising:
Current signal in a plurality of USB main line is sampled and described current signal is converted to the sampling module of voltage signal;
Carry out the amplification module that described voltage signal amplifies;
The comparison module that described voltage signal is compared; With
Receive the more described voltage signal of described comparison module and produce after the level signal of expression real-time current state and detect electric current and the CPU that selects the switch control module on a plurality of USB branch roads of control is arranged after exceeding set point; Wherein,
Described sampling module, described amplification module and described comparison module are connected successively, and described comparison module also connects described CPU.
2. described circuit as claimed in claim 1, it is characterized in that, described sampling module further comprises first resistance and second resistance of two parallel connections, wherein, circuit after the described parallel connection, one end connects 5V supply network and described amplification module, and the other end connects laod network and the described amplification module of two-way or multichannel USB.
3. described circuit as claimed in claim 2, it is characterized in that, described amplification module further comprises: first amplifier, the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance, wherein, the negative input of described first amplifier is connected with laod network by described the 3rd resistance and forms feedback circuit by described the 5th resistance and its output, and the electrode input end of described first amplifier is connected with supply network by described the 4th resistance and passes through described the 6th grounding through resistance.
4. described circuit as claimed in claim 3, it is characterized in that, described comparison module further comprises: second amplifier, the 7th resistance, the 8th resistance, the 9th resistance and voltage-stabiliser tube, wherein, the electrode input end of described second amplifier is connected with the output of described first amplifier by described the 7th resistance, the negative input of described second amplifier is connected with reference voltage by described the 8th resistance, the output of described second amplifier connects the universal input/output interface GPIO_IN of CPU by the 9th resistance, and connects described voltage-stabiliser tube between the universal input/output interface GPIO_IN of described the 9th resistance and described CPU.
5. described circuit as claimed in claim 1 is characterized in that, described switch control module further comprises: the NPN pipe, the tenth resistance, the 11 resistance, the 16 resistance, the 17 resistance, the 18 resistance, the 19 resistance, electric capacity and P channel MOS tube Q9, wherein, an end of described the 17 resistance connects the universal input/output interface GPIO_IN of described CPU, the other end connects the base stage of described NPN pipe, and wherein, the two ends of described the 18 resistance connect the base stage and the emitter of described NPN pipe respectively;
The collector electrode of described NPN pipe connects an end of described the tenth resistance and an end of described the 16 resistance, the other end of described the 16 resistance is connected with the grid of described P channel MOS tube Q9 by described the 11 resistance, and the other end of described the 16 resistance is also simultaneously by described the 19 resistance, and described electric capacity connects with the source class of described P channel MOS tube Q9;
The other end of described the tenth resistance all is connected with described laod network with the source class of described P channel MOS tube Q9, and the drain electrode of described P channel MOS tube Q9 connects described external USB device port USB_PORT1.
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| CN2009202049036U CN201536253U (en) | 2009-09-18 | 2009-09-18 | USB overcurrent detection and control circuit |
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| CN2009202049036U CN201536253U (en) | 2009-09-18 | 2009-09-18 | USB overcurrent detection and control circuit |
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| CN102591832A (en) * | 2011-01-12 | 2012-07-18 | 深圳艾科创新微电子有限公司 | Current limiting circuit and method of universal serial bus |
| CN102780512A (en) * | 2012-06-20 | 2012-11-14 | 光一科技股份有限公司 | Protective circuit for preventing radio station from uninterrupted transmission |
| CN102938797A (en) * | 2012-11-05 | 2013-02-20 | Tcl通讯（宁波）有限公司 | Current detection and control device for mobile terminal |
| CN102938554A (en) * | 2011-08-15 | 2013-02-20 | 上海普锐马电子有限公司 | High-power adjustable clamping circuit for automobile jammer |
| WO2016115703A1 (en) * | 2015-01-22 | 2016-07-28 | 华为技术有限公司 | Current-limiting protection circuit and electronic device |
| CN107546724A (en) * | 2017-07-17 | 2018-01-05 | 北方电子研究院安徽有限公司 | A kind of input overcurrent protective device |
| CN109417283A (en) * | 2016-05-16 | 2019-03-01 | 赛普拉斯半导体公司 | The adjustable over-current detector circuit of universal serial bus (USB) equipment |
| CN110494759A (en) * | 2017-05-18 | 2019-11-22 | 赛普拉斯半导体公司 | Current sense in USB power control analog subsystem |
| CN112165082A (en) * | 2020-09-21 | 2021-01-01 | 苏州浩创信息科技有限公司 | Interface protection circuit and wearable intelligent device applying same |
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| CN102591832A (en) * | 2011-01-12 | 2012-07-18 | 深圳艾科创新微电子有限公司 | Current limiting circuit and method of universal serial bus |
| CN102591832B (en) * | 2011-01-12 | 2016-08-03 | 深圳艾科创新微电子有限公司 | A kind of USB (universal serial bus) current-limiting circuit |
| CN102938554A (en) * | 2011-08-15 | 2013-02-20 | 上海普锐马电子有限公司 | High-power adjustable clamping circuit for automobile jammer |
| CN102780512A (en) * | 2012-06-20 | 2012-11-14 | 光一科技股份有限公司 | Protective circuit for preventing radio station from uninterrupted transmission |
| CN102938797A (en) * | 2012-11-05 | 2013-02-20 | Tcl通讯（宁波）有限公司 | Current detection and control device for mobile terminal |
| CN102938797B (en) * | 2012-11-05 | 2015-09-23 | Tcl通讯（宁波）有限公司 | A kind of current detection controller of mobile terminal |
| WO2016115703A1 (en) * | 2015-01-22 | 2016-07-28 | 华为技术有限公司 | Current-limiting protection circuit and electronic device |
| US10411464B2 (en) | 2015-01-22 | 2019-09-10 | Huawei Technologies Co., Ltd. | Current-limiting protection circuit and electronic device |
| CN109417283A (en) * | 2016-05-16 | 2019-03-01 | 赛普拉斯半导体公司 | The adjustable over-current detector circuit of universal serial bus (USB) equipment |
| CN109417283B (en) * | 2016-05-16 | 2020-06-12 | 赛普拉斯半导体公司 | Adjustable overcurrent detector circuit for Universal Serial Bus (USB) device |
| CN111650423A (en) * | 2016-05-16 | 2020-09-11 | 赛普拉斯半导体公司 | Adjustable overcurrent detector circuit for Universal Serial Bus (USB) device |
| US10847964B2 (en) | 2016-05-16 | 2020-11-24 | Cypress Semiconductor Corporation | Adjustable over-current detector circuit for universal serial bus (USB) devices |
| CN111650423B (en) * | 2016-05-16 | 2022-06-03 | 赛普拉斯半导体公司 | Adjustable overcurrent detector circuit for Universal Serial Bus (USB) device |
| CN110494759A (en) * | 2017-05-18 | 2019-11-22 | 赛普拉斯半导体公司 | Current sense in USB power control analog subsystem |
| CN107546724A (en) * | 2017-07-17 | 2018-01-05 | 北方电子研究院安徽有限公司 | A kind of input overcurrent protective device |
| CN112165082A (en) * | 2020-09-21 | 2021-01-01 | 苏州浩创信息科技有限公司 | Interface protection circuit and wearable intelligent device applying same |
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