CN203858536U - USB interface and voltage-stabilizing and current-limiting circuit in same - Google Patents
USB interface and voltage-stabilizing and current-limiting circuit in same Download PDFInfo
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- CN203858536U CN203858536U CN201420288291.4U CN201420288291U CN203858536U CN 203858536 U CN203858536 U CN 203858536U CN 201420288291 U CN201420288291 U CN 201420288291U CN 203858536 U CN203858536 U CN 203858536U
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Abstract
The utility model provides a USB interface and a voltage-stabilizing and current-limiting circuit in the USB interface. The voltage-stabilizing and current-limiting circuit comprises a first transistor, a second transistor, a voltage feedback unit, a first operational amplifier, a current-voltage conversion unit and a second operational amplifier, wherein the first connection end and the control end of the second transistor are connected with the first connection end and the control end of the first transistor respectively, and the second connection end of the second transistor is connected with the output end of the voltage-stabilizing and current-limiting circuit; the voltage feedback unit provides a feedback voltage reflecting the voltage of the output end; the first input end of the first operational amplifier is connected with the feedback voltage, the second input end of the first operational amplifier is connected with a first reference voltage, and the output end of the first operational amplifier is connected with the control end of the first transistor; the current-voltage conversion unit generates a conversion voltage proportional to a current flowing through the first transistor; the first input end of the second operational amplifier is connected with the conversion voltage, the second input end of the second operational amplifier is connected with a second reference voltage, and the output end of the second operational amplifier is connected with the control end of the first transistor. Compared with the prior art, the voltage-stabilizing and current-limiting circuit can perform voltage-stabilizing and current-limiting protection on the USB interface.
Description
[technical field]
The utility model relates to circuit design field, particularly a kind of USB (Universal Serial Bus, USB (universal serial bus)) interface and voltage stabilizing current-limiting circuit wherein.
[background technology]
Day by day universal along with usb data transmission technology, increasing electronic equipment option and installment USB interface realizes the transport communication of itself and external unit.At present; to USB device, power supply all adopts the directly mode of power supply to host computer system; this power supply mode without any protection and measuring ability; because general USB interface has specified electric current fan-out capability; therefore; once there is the situations such as internal short-circuit in USB device, cause USB interface overcurrent, will cause the damage of electronic product.In addition, too much if USB device takies electric current, also likely can cause host computer system lower voltage, thereby affect the normal work of whole system.
Therefore, be necessary to provide a kind of improved technical scheme to protect USB interface.
[utility model content]
The purpose of this utility model is to provide a kind of USB interface and voltage stabilizing current-limiting circuit wherein, and it can be protected USB interface.
In order to address the above problem, according to an aspect of the present utility model, the utility model provides a kind of voltage stabilizing current-limiting circuit, and it comprises the first transistor, transistor seconds, the first operational amplifier, the second operational amplifier, voltage feedback unit and current-voltage converting unit.The first link of described transistor seconds is connected with control end with the first link of described the first transistor respectively with control end, the second link of described transistor seconds is connected with the output terminal of described voltage stabilizing current-limiting circuit, and described the first transistor produces and the proportional image current of the electric current that flows through described transistor seconds; Described voltage feedback unit provides the feedback voltage of the described output end voltage of reflection; The first input end of described the first operational amplifier is connected with described feedback voltage, and its second input end is connected with the first reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds; Described current-voltage converting unit for generation of to the proportional changing voltage of described image current; The first input end of described the second operational amplifier is connected with described changing voltage, and its second input end is connected with described the second reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds.
Further, described voltage stabilizing current-limiting circuit also comprises isobaric control module, and described isobaric control module equates for controlling the voltage of the second link of the first transistor and the second link of transistor seconds.
Further, described isobaric control module comprises the 3rd transistor and the 3rd operational amplifier, the first input end of described the 3rd operational amplifier is connected with the second link of the first transistor, its second input end is connected with the second link of transistor seconds, and its output terminal is connected with described the 3rd transistorized control end; Described the 3rd transistorized the first link is connected with the second link of described the first transistor, and its second link is connected with described current-voltage converting unit.
Further, the flow through ratio of the image current of described the first transistor and the electric current of the described transistor seconds of flowing through equals the ratio of the physical dimension of described the first transistor and the physical dimension of described transistor seconds.
Further, described the first transistor, transistor seconds and the 3rd transistor are all PMOS transistor, and described the first link is source electrode, and described the second link is drain electrode, and described control end is grid, and described physical dimension is channel width-over-length ratio.
Further, described the first transistor, transistor seconds and the 3rd transistor are all PNP transistor,
Described the first link is emitter, and described the second link is collector, and described control end is base stage, and described physical dimension is emitter area.
Further, the first link of described the first transistor and the first link of transistor seconds are all connected with input voltage, described voltage feedback unit comprises the first divider resistance and the second divider resistance being series at successively between ground contacts and described output terminal, and the connected node between the first divider resistance and the second divider resistance is exported described feedback voltage; Described current-voltage converting unit comprises the external resistance being connected between described the 3rd transistorized the second link and ground node, and described changing voltage is exported in one end that external resistance is not connected with ground node.
Further, the difference of described the second operational amplifier based on the second reference voltage and changing voltage exported the control end that the second control signal is controlled described the first transistor and transistor seconds, maximum output current
RSET is the resistance of external resistance;
The burning voltage of output voltage VO UT is
Work as input voltage
Time, the complete conducting of transistor seconds, output voltage VO UT=VCC-IOUT * RON, works as input voltage
Time, output voltage
Wherein, R1 is the resistance value of the first divider resistance, R2 is the resistance value of the second divider resistance, IOUT is the output current of output terminal, VREF1 is the magnitude of voltage of the first reference voltage, VREF2 is the magnitude of voltage of the second reference voltage, the conduction resistance value that RON is described transistor seconds, the ratio of the channel width-over-length ratio that K is described the first transistor and the channel width-over-length ratio of described transistor seconds.
Further, described voltage stabilizing current-limiting circuit also comprises status display circuit, described status display circuit comprises condition judgement module and LED, the corresponding signal that drives of the duty of described condition judgement module based on described feedback voltage and changing voltage decision circuit output; Described LED, under the driving of different driving signals, carries out different LED and shows.
Further, described condition judgement module has set in advance the first reference voltage V REF1, the second reference voltage V REF2, the 3rd reference voltage V REF3 and the 4th reference voltage V REF4, and described LED comprises one or more LED lamp.When VFB > VREF1, described condition judgement module decision circuit is in overvoltage condition; When VFB < VREF3, described condition judgement module decision circuit is in short-circuit condition or brownout state; When VREF3 < VFB < VREF1, described condition judgement module decision circuit is in normal operating conditions, when VSET > VREF2, described condition judgement module decision circuit is in over-current state; When VSET < VREF4, described condition judgement module decision circuit is in light condition or the less state of load; When VREF4 < VSET < VREF2, described condition judgement module decision circuit is in normal operating conditions, and described condition judgement module drives signal to LED according to result of determination output accordingly.
According to another aspect of the present utility model, the utility model provides a kind of USB interface, and it comprises voltage stabilizing current-limiting circuit, and the output terminal of described voltage stabilizing current-limiting circuit is connected with the feeder ear of described USB interface.Described voltage stabilizing current-limiting circuit comprises the first transistor, transistor seconds, the first operational amplifier, the second operational amplifier, voltage feedback unit and current-voltage converting unit.The first link of described transistor seconds is connected with control end with the first link of described the first transistor respectively with control end, the second link of described transistor seconds is connected with the output terminal of described voltage stabilizing current-limiting circuit, and described the first transistor produces and the proportional image current of the electric current that flows through described transistor seconds; Described voltage feedback unit provides the feedback voltage of the described output end voltage of reflection; The first input end of described the first operational amplifier is connected with described feedback voltage, and its second input end is connected with the first reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds; Described current-voltage converting unit for generation of to the proportional changing voltage of described image current; The first input end of described the second operational amplifier is connected with described changing voltage, and its second input end is connected with described the second reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds.
Compared with prior art, the utility model is by the feedback control loop output voltage to voltage stabilizing current-limiting circuit respectively, and output current is adjusted control, thereby USB interface is carried out to voltage stabilizing and current-limiting protection.
[accompanying drawing explanation]
In order to be illustrated more clearly in the technical scheme of the utility model embodiment, below the accompanying drawing of required use during embodiment is described is briefly described, apparently, accompanying drawing in the following describes is only embodiment more of the present utility model, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.Wherein:
Fig. 1 is the circuit diagram of the utility model voltage stabilizing current-limiting circuit in one embodiment.
[embodiment]
For above-mentioned purpose of the present utility model, feature and advantage can be become apparent more, below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.
Alleged " embodiment " or " embodiment " refers to special characteristic, structure or the characteristic that can be contained at least one implementation of the utility model herein.Different local in this manual " in one embodiment " that occur not all refer to same embodiment, neither be independent or the embodiment mutually exclusive with other embodiment optionally.Unless stated otherwise, the word that connection herein, the expression that is connected, joins are electrically connected all represents to be directly or indirectly electrical connected.In this article, term " transistor " comprises bipolar transistor and MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, metal-oxide half field effect transistor).
Fig. 1 is the circuit diagram of the utility model voltage stabilizing current-limiting circuit in one embodiment.Described voltage stabilizing current-limiting circuit comprises the first transistor M1, transistor seconds M2, the first operational amplifier VA, the second operational amplifier CA, voltage feedback unit 110 and current-voltage converting unit 120.
Described transistor seconds M2 is used as output transistor, and its first link is connected with input voltage VCC, and its second link is connected with the output terminal VOUT of described voltage stabilizing current-limiting circuit, and this output terminal VOUT can be connected with the feeder ear of USB interface.
The first link of described the first transistor M1 is connected with control end with the first link of described transistor seconds M2 respectively with control end, to form current mirror circuit, thereby described the first transistor M1 is produced and the proportional image current of the electric current that flows through described transistor seconds M2.Described voltage feedback unit 110 provides the feedback voltage V FB of the described output terminal VOUT voltage of reflection.The first input end of described the first operational amplifier VA is connected with described feedback voltage V FB, and its second input end is connected with the first reference voltage V REF1, and its output terminal is connected with the control end of transistor seconds M2 with the first transistor M1.Described current-voltage converting unit 120 is for generation of changing voltage VSET proportional to described image current.The first input end of described the second operational amplifier CA is connected with described changing voltage VSET, and its second input end is connected with described the second reference voltage V REF2, and its output terminal is connected with the control end of transistor seconds M2 with the first transistor M1.
Described voltage stabilizing current-limiting circuit also comprises isobaric control module 130, and it equates for controlling the voltage of the second link of the first transistor M1 and the second link of transistor seconds M2.In the embodiment shown in fig. 1, described isobaric control module 130 comprises the 3rd transistor M3 and the 3rd operational amplifier MA, the first input end of described the 3rd operational amplifier MA is connected with the second link of the first transistor M1, its second input end is connected with the second link of transistor seconds M2, its output terminal is connected with the control end of described the 3rd transistor M3, the first link of described the 3rd transistor M3 is connected with the second link of described the first transistor M1, its second link is connected with described current-voltage converting unit 120, difference output the 3rd control signal CO3 of the second link voltage of the second link voltage of described the 3rd operational amplifier MA based on the first transistor M1 and transistor seconds M2 controls the 3rd transistor M3, the 3rd transistor M3 and the 3rd operational amplifier MA form feedback control loop, the voltage of the second link of the first transistor M1 and the second link of transistor seconds M2 is equated, thereby the mirror that guarantees the first transistor M1 and transistor seconds M2 is more accurate, to improve the current detection accuracy of circuit backfeed loop hereinafter.
Below with reference to Fig. 1, the principle of work of the voltage stabilizing current-limiting circuit in the utility model that is specifically situated between.
In Fig. 1, described the first transistor M1, transistor seconds M2 and the 3rd transistor M2 are PMOS transistor, and described the first link is source electrode, and described the second link is drain electrode, and described control end is grid; Described voltage feedback unit 110 comprises the first divider resistance R1 and the second divider resistance R2 being series at successively between ground contacts and output terminal VOUT, and the voltage of the connected node between the first divider resistance R1 and the second divider resistance R2 is described feedback voltage V FB; Described current-voltage converting unit 120 comprises and is connected in the second link of described the 3rd transistor M3 and the external resistance R SET between ground node, the described image current that flows through described the first transistor M1 and the 3rd transistor M3 forms pressure drop through external resistance R SET on this resistance, and the voltage of one end that external resistance R SET is not connected with ground node is described changing voltage VSET; The image current that flows through described the first transistor M1 and the ratio of the electric current of the described transistor seconds M2 that flows through equal the ratio of the channel width-over-length ratio of described the first transistor M1 and the channel width-over-length ratio of described transistor seconds M2.
Voltage feedback unit 110, the first operational amplifier VA and transistor seconds M2 form voltage feedback loop.The difference of described the first operational amplifier VA based on the first reference voltage V REF1 and feedback voltage V FB exported the control end that the first control signal CO1 controls described the first transistor M1 and transistor seconds M2.The burning voltage of output voltage VO UT is
Work as input voltage
Time, the complete conducting of described transistor seconds M2, output voltage VO UT=VCC-IOUT * RON;
Work as input voltage
Time, under the control of this voltage feedback loop, output voltage
Wherein, R1 is the resistance value of the first divider resistance R1, R2 is the resistance value of the second divider resistance R2, IOUT is that (it is provided by transistor seconds M2 for the output current of output terminal VOUT, be the electric current that the output current of output terminal VOUT equals to flow through described transistor seconds M2), VREF1 is the magnitude of voltage of the first reference voltage V REF1, RON is the conduction resistance value of described transistor seconds M2, VREF2 is the magnitude of voltage of the second reference voltage V REF2, and K is the ratio of the channel width-over-length ratio of described the first transistor M1 and the channel width-over-length ratio of described transistor seconds M2.Like this, the voltage stabilizing current-limiting circuit in the utility model has just realized the voltage stabilizing of USB interface and current-limiting protection.
The second operational amplifier CA, the first transistor M1, transistor seconds M2, isobaric control module 130, current-voltage conversion circuit 120 have formed current feedback loop.The difference of described the second operational amplifier CA based on the second reference voltage V REF2 and changing voltage VSET exported the control end that the second control signal CO2 controls described the first transistor M1 and transistor seconds M2.Under the control of this current feedback loop, the maximum output current of described output terminal VOUT output:
In another embodiment, described the first transistor M1, transistor seconds M2 and the 3rd transistor M3 can be also PNP transistor, and described the first link is emitter, and the second link is collector, and control end is base stage.Image current and the ratio of the electric current of the described transistor seconds M2 that flows through of described the first transistor M1 of flowing through equals the ratio of the emitter area of described the first transistor M1 and the emitter area of described transistor seconds M2.
In summary, flow through image current and the ratio of the electric current of the described transistor seconds M2 that flows through of described the first transistor M1 equals the ratio of the physical dimension of described the first transistor M1 and the physical dimension of described transistor seconds M2.When described the first transistor M1, transistor seconds M2 and the 3rd transistor M3 are PNP transistor, described physical dimension is emitter area; When described the first transistor M1, transistor seconds M2 and the 3rd transistor M3 are PMOS transistor, described physical dimension is channel width-over-length ratio.
It should be noted that, the first reference voltage V REF1 and the 2nd VREF2 can be set as equal voltage, also can unequal voltage.
For the ease of user, get information about the working condition (being output voltage and the output current situation of output terminal VOUT) of voltage stabilizing current-limiting circuit in the utility model, voltage stabilizing current-limiting circuit in Fig. 1 also comprises status display circuit 140, and described status display circuit 140 comprises condition judgement module (not shown) and LED.
Duty (be the duty of output terminal VOUT) output corresponding the drive signal of described condition judgement module based on described feedback voltage V FB (its reflection output voltage VO UT) and changing voltage VSET (its reflection output current IO UT) decision circuit, described LED is driving under the driving of signal, carry out corresponding LED demonstration, thereby facilitate user according to the duty of the show state decision circuit of LED.
In one embodiment, described condition judgement module has set in advance reference voltage VREF, this reference voltage VREF comprises the first reference voltage V REF1, the second reference voltage V REF2, the 3rd reference voltage V REF3 and the 4th reference voltage V REF4, and described LED comprises LED1 and LED2.When VFB > VREF1, described condition judgement module decision circuit is in overvoltage condition; When VFB < VREF3, described condition judgement module decision circuit is in short-circuit condition or brownout state; When VREF3 < VFB < VREF1, described condition judgement module decision circuit is in normal operating conditions.When VSET > VREF2, described condition judgement module decision circuit is in over-current state; When VSET < VREF4, described condition judgement module decision circuit is in light condition or the less state of load; When VREF4 < VSET < VREF2, described condition judgement module decision circuit is in normal operating conditions.Described condition judgement module is according to the corresponding signal that drives of result of determination output to LED, and when circuit is during in light condition, described condition judgement module drive LED1 goes out, and LED2 is bright; When circuit is during in normal operating conditions, described condition judgement module drive LED1 is bright, and LED2 goes out; When circuit is during in over-current state, described condition judgement module drive LED1 goes out, LED2 flicker; When circuit is during in short-circuit condition or brownout state, described condition judgement module drive LED1 and LED2 go out.
In other embodiments, described reference voltage V REF can comprise 1,2,3,5 or more different reference voltage, so that the duty of described circuit is carried out to different divisions, corresponding described LED also can comprise 3,4 or more LED lamp, so that LED can be provided with a plurality of different show states.In a preferred embodiment, described LED comprises a color-changing light-emitting diode, this color-changing light-emitting diode under the driving of described condition judgement module in different coloured light show states (such as, ruddiness show state, green glow show state etc.), thereby save the usage quantity of LED lamp, reduce circuit cost.
In sum, voltage stabilizing current-limiting circuit in the utility model is passed through three feedback control loops respectively to output voltage VO UT, the proportional mirror image of output current IO UT and electric current is adjusted control, thereby realize stable Voltage-output and accurate current detecting, simultaneously, because it is provided with status display circuit 140, this status display circuit 140 carrys out the duty of decision circuit based on output voltage VO UT and output current IO UT, and represent different duties by the different show states of LED, thereby the duty of the convenient show state decision circuit from LED.
According to an aspect of the present utility model, the utility model provides a USB interface, and this USB interface comprises above-described voltage stabilizing current-limiting circuit, and the output terminal of described voltage stabilizing current-limiting circuit is connected with the feeder ear of described USB interface.So not only USB interface output current can overcurrent, and it is constant that output voltage also can keep.Meanwhile, owing to can carrying out state demonstration, when breaking down, can remind to fix a breakdown.
In the utility model, " connection ", be connected, word that the expression such as " company ", " connecing " is electrical connected, if no special instructions, represent direct or indirect electric connection.
It is pointed out that being familiar with any change that person skilled in art does embodiment of the present utility model does not all depart from the scope of claims of the present utility model.Correspondingly, the scope of claim of the present utility model is also not limited only to previous embodiment.
Claims (10)
1. a voltage stabilizing current-limiting circuit, is characterized in that, it comprises the first transistor, transistor seconds, the first operational amplifier, the second operational amplifier, voltage feedback unit and current-voltage converting unit,
The first link of described transistor seconds is connected with control end with the first link of described the first transistor respectively with control end, the second link of described transistor seconds is connected with the output terminal of described voltage stabilizing current-limiting circuit, and described the first transistor produces and the proportional image current of the electric current that flows through described transistor seconds;
Described voltage feedback unit provides the feedback voltage of the described output end voltage of reflection;
The first input end of described the first operational amplifier is connected with described feedback voltage, and its second input end is connected with the first reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds;
Described current-voltage converting unit for generation of to the proportional changing voltage of described image current;
The first input end of described the second operational amplifier is connected with described changing voltage, and its second input end is connected with the second reference voltage, and its output terminal is connected with the control end of the first transistor and transistor seconds.
2. voltage stabilizing current-limiting circuit according to claim 1, is characterized in that, it also comprises isobaric control module, and described isobaric control module equates for controlling the voltage of the second link of the first transistor and the second link of transistor seconds.
3. voltage stabilizing current-limiting circuit according to claim 2, is characterized in that, described isobaric control module comprises the 3rd transistor and the 3rd operational amplifier,
The first input end of described the 3rd operational amplifier is connected with the second link of the first transistor, and its second input end is connected with the second link of transistor seconds, and its output terminal is connected with described the 3rd transistorized control end;
Described the 3rd transistorized the first link is connected with the second link of described the first transistor, and its second link is connected with described current-voltage converting unit.
4. voltage stabilizing current-limiting circuit according to claim 3, it is characterized in that, the image current of the described the first transistor of flowing through and the ratio of the electric current of the described transistor seconds of flowing through equal the ratio of the physical dimension of described the first transistor and the physical dimension of described transistor seconds.
5. voltage stabilizing current-limiting circuit according to claim 4, is characterized in that,
Described the first transistor, transistor seconds and the 3rd transistor are all PMOS transistor,
Described the first link is source electrode, and described the second link is drain electrode, and described control end is grid,
Described physical dimension is channel width-over-length ratio.
6. voltage stabilizing current-limiting circuit according to claim 4, is characterized in that,
Described the first transistor, transistor seconds and the 3rd transistor are all PNP transistor,
Described the first link is emitter, and described the second link is collector, and described control end is base stage,
Described physical dimension is emitter area.
7. voltage stabilizing current-limiting circuit according to claim 5, is characterized in that,
The first link of described the first transistor and the first link of transistor seconds are all connected with input voltage,
Described voltage feedback unit comprises the first divider resistance and the second divider resistance being series at successively between ground contacts and described output terminal, and the connected node between the first divider resistance and the second divider resistance is exported described feedback voltage;
Described current-voltage converting unit comprises the external resistance being connected between described the 3rd transistorized the second link and ground node, and described changing voltage is exported in one end that external resistance is not connected with ground node.
8. voltage stabilizing current-limiting circuit according to claim 7, is characterized in that,
The difference of described the second operational amplifier based on the second reference voltage and changing voltage exported the control end that the second control signal is controlled described the first transistor and transistor seconds, maximum output current
rSET is the resistance of external resistance;
The burning voltage of output voltage VO UT is
work as input voltage
time, the complete conducting of transistor seconds, output voltage VO UT=VCC-IOUT * RON, works as input voltage
time, output voltage
Wherein, R1 is the resistance value of the first divider resistance, R2 is the resistance value of the second divider resistance, IOUT is the output current of output terminal, VREF1 is the magnitude of voltage of the first reference voltage, VREF2 is the magnitude of voltage of the second reference voltage, the conduction resistance value that RON is described transistor seconds, the ratio of the channel width-over-length ratio that K is described the first transistor and the channel width-over-length ratio of described transistor seconds.
9. voltage stabilizing current-limiting circuit according to claim 7, is characterized in that, it also comprises status display circuit, and described status display circuit comprises condition judgement module and LED,
The corresponding signal that drives of the duty of described condition judgement module based on described feedback voltage and changing voltage decision circuit output;
Described LED, under the driving of different driving signals, carries out different LED and shows,
Described condition judgement module has set in advance the first reference voltage V REF1, the second reference voltage V REF2, the 3rd reference voltage V REF3 and the 4th reference voltage V REF4, and described LED comprises one or more LED lamp,
When VFB > VREF1, described condition judgement module decision circuit is in overvoltage condition; When VFB < VREF3, described condition judgement module decision circuit is in short-circuit condition or brownout state; When VREF3 < VFB < VREF1, described condition judgement module decision circuit is in normal operating conditions,
When VSET > VREF2, described condition judgement module decision circuit is in over-current state; When VSET < VREF4, described condition judgement module decision circuit is in light condition or the less state of load; When VREF4 < VSET < VREF2, described condition judgement module decision circuit is in normal operating conditions,
Described condition judgement module drives signal to LED according to result of determination output accordingly.
10. a USB interface, is characterized in that, it comprises the arbitrary described voltage stabilizing current-limiting circuit of claim 1-9, and the output terminal of described voltage stabilizing current-limiting circuit is connected with the feeder ear of described USB interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420288291.4U CN203858536U (en) | 2014-05-30 | 2014-05-30 | USB interface and voltage-stabilizing and current-limiting circuit in same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420288291.4U CN203858536U (en) | 2014-05-30 | 2014-05-30 | USB interface and voltage-stabilizing and current-limiting circuit in same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203858536U true CN203858536U (en) | 2014-10-01 |
Family
ID=51608378
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420288291.4U Expired - Lifetime CN203858536U (en) | 2014-05-30 | 2014-05-30 | USB interface and voltage-stabilizing and current-limiting circuit in same |
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| CN (1) | CN203858536U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104020810A (en) * | 2014-05-30 | 2014-09-03 | 无锡中星微电子有限公司 | USB interface and voltage stabilizing and current limiting circuit thereof |
| CN104597957A (en) * | 2015-02-04 | 2015-05-06 | 成都市宏山科技有限公司 | Current conversion circuit |
-
2014
- 2014-05-30 CN CN201420288291.4U patent/CN203858536U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104020810A (en) * | 2014-05-30 | 2014-09-03 | 无锡中星微电子有限公司 | USB interface and voltage stabilizing and current limiting circuit thereof |
| CN104597957A (en) * | 2015-02-04 | 2015-05-06 | 成都市宏山科技有限公司 | Current conversion circuit |
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Address after: 214028 10th Floor, Area A, 530 Building, Qingyuan Road, Taihu International Science Park, Wuxi New District, Jiangsu Province Patentee after: WUXI ZHONGGAN MICROELECTRONIC CO., LTD. Address before: 214028 10th Floor, Area A, 530 Building, Qingyuan Road, Taihu International Science Park, Wuxi New District, Jiangsu Province Patentee before: Wuxi Vimicro Co., Ltd. |
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