CN101099079A - Current detection circuit, photoreceiver using the same, light emission control device, and electronic device using the same - Google Patents
Current detection circuit, photoreceiver using the same, light emission control device, and electronic device using the same Download PDFInfo
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- CN101099079A CN101099079A CNA2006800017650A CN200680001765A CN101099079A CN 101099079 A CN101099079 A CN 101099079A CN A2006800017650 A CNA2006800017650 A CN A2006800017650A CN 200680001765 A CN200680001765 A CN 200680001765A CN 101099079 A CN101099079 A CN 101099079A
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Abstract
There is provided a current detection circuit capable of performing a stable current detection. A first transistor (Q1) is provided on a current path of a photo transistor (210). A bias current path (12) includes a bias switch (SW1) and a first bias resistor (Rbias1) connected in series and arranged in parallel to a main current path (10) including the photo transistor (210). A second transistor (Q2) constitutes a current mirror circuit together with the first transistor (Q1) and generates a second current (Iq2) obtained by multiplying a first current (Iq1) flowing in the first transistor (Q1) by a predetermined number. The second current (Iq2) is charged to a charge capacitor (Cchg) and converted into voltage. The bias current path (12) is turned ON before photoreception start of the photo transistor (210) and is turned OFF when a predetermined time has elapsed after start of photoreception by the photo transistor (210).
Description
Technical field
The present invention relates to detect the current detection circuit of the electric current that flows through in the sensitive device and the luminous emission control device of controlling light emitting device.
Background technology
In various electronic equipments, detect light, and carry out and detected light income corresponding signal process from outside incident.As such example, can list the infrared rays receiver of illuminance transducer, infrared remote controller etc.As the sensitive device that receives light, phototransistor (phototransistor), photodiode (photodiode), CCD (charge-coupled image sensor) etc. are widely used.
Phototransistor and photodiode output and the corresponding electric current of light income.Therefore, infrared rays receiver amplifies the electric current that flows through in these sensitive devices, perhaps carries out voltage transformation etc., carries out signal Processing.For example, patent documentation 1 discloses the infrared rays receiver of infrared remote sensing device (remote sensor), discloses the structure of light receiving circuit among its Fig. 3.In addition, patent documentation 2 discloses the structure of using the light receiving circuit of operational amplifier.
In addition, in various electronic equipments, detect light, and carry out and detected light income corresponding signal process from outside incident.As such example, can list the light emitting control of camera flashlamp.Specifically, detect the light that the light that sends from flashlamp reflects through subject etc., when reflected light reaches predeterminated level, extinguish flashlamp (below be also referred to as luminescent device).In patent documentation 3, record correlation technique.
Patent documentation 1: the spy opens flat 6-188835 communique
Patent documentation 2: the spy opens the 2005-216984 communique
Patent documentation 3: the spy opens the 2005-10366 communique
Summary of the invention
(inventing problem to be solved)
In such infrared rays receiver, want sometimes only to detect light income in the predetermined moment.As an example, the light emitting control of the flashlamp in the portable telephone terminal of consideration camera or band camera.The fluorescent lifetime of flashlamp carries out following control: to reference object thing illumination flash, detect the light that is reflected, stop the luminous of flashlamp in the moment that has predetermined light quantity to reflect.Therefore, if carry out the detection of light before flashlamp is luminous, the then original light of not detected sunshine or fluorescent light of not answering is also detected, so produce the problem that can not carry out accurate light emission control.
Problem 2.
In addition, inquire in such equipment and to use situation about generating in order to receive reflected light with sensitive devices such as the phototransistor of the corresponding photocurrent of light income, photodiodes.In order to use these sensitive devices to carry out above-mentioned light emitting control, consider photocurrent is carried out integration, when reaching predetermined value, make the luminous method that stops.Here, as the method for carrying out the integration of photocurrent simply, consider to make photocurrent to flow into the method that electric capacity charges.In this case, current potential and the threshold voltage that electric capacity presented compared, luminescent device is extinguished based on this comparative result.
Yet the current potential that electric capacity presented reduces because of discharge waits after reaching threshold voltage sometimes, or is subjected to The noise and change.In this case, when current potential that electric capacity presented drops to when being lower than threshold voltage, luminescent device will be luminous once more.Then, when because of after the luminous current potential that electric capacity is presented reaches threshold voltage again, luminously stop once more, may carry out so luminous and stop luminous repeatedly.
The present invention finishes in view of such problem, and one of its purpose is to provide a kind of can be applicable to the infrared rays receiver that is subjected to light at predetermined instant, and can carry out the current detection circuit of stable current detecting.
In addition, another object of the present invention is to provide a kind of luminous emission control device that stops that making luminescent device reliably.
(being used to solve the means of problem)
A scheme of the present invention, be detect with sensitive device that detection terminal is connected in the current detection circuit of the electric current that flows through.This current detection circuit comprises: be arranged on the 1st transistor on the current path of sensitive device; Be arranged in parallel the bias current path of the control that can switch on and off with the primary current path that comprises sensitive device; Constitute current mirroring circuit with the 1st transistor, the electric current that flows through in the 1st transistor is become 2nd transistor of pre-determined factor times back as the output of this current detection circuit.The bias current path begins preceding connection at the light that is subjected to of sensitive device.The bias current path also can comprise the 1st biasing resistor and the biased witch ground that are connected in series and constitute.
According to this scheme, before being subjected to light, the bias current path is connected, flow through electric current, thereby flow through electric current in the 1st transistor.Its result, the 1st transistor is biased in constant current region, can guarantee that the voltage of detection terminal is almost steady state value, can carry out stable current detecting.
The bias current path can begin to be subjected to light to disconnect through after the schedule time from sensitive device.At this moment, after disconnecting the bias current path, become and only detect the electric current that flows through in the sensitive device, so can carry out current detecting more accurately.
Current detection circuit can also comprise the light that is subjected at sensitive device is begun the latch cicuit that control signal that the front signal level changes latchs the schedule time, with the output signal of this latch cicuit as the signal that switches on and off that is used to control the bias current path.
Current detection circuit can also be included in the 2nd set biasing resistor between above-mentioned the 1st transistor on the primary current path and the above-mentioned detection terminal.Can also comprise the by-pass switch with above-mentioned the 2nd biasing resistor bypass, by-pass switch begins preceding connection at the light that is subjected to of sensitive device.
By the 2nd biasing resistor is set, the impedance that improves primary current path during can be before begun by light can reduce the current sinking of circuit.
Current detection circuit can make the electric current that flows through in the 2nd transistor that electric capacity is charged, and converts voltage to and exports.At this moment, can carry out integration, export as voltage to the photocurrent that generates by sensitive device.
Current detection circuit can be integrated on a Semiconductor substrate.So-called " integrating ", all structure important documents that comprise circuit all are formed on the situation on the Semiconductor substrate, and the primary structure important document of circuit situation about being integrated, also can a part of resistance, electric capacity etc. be arranged on the outside of Semiconductor substrate for the regulating circuit constant.Integrated by current detection circuit is carried out as a LSI, circuit area can be reduced, and the homogeneous of circuit component characteristics such as transistor, resistance can be guaranteed.
Another program of the present invention is an infrared rays receiver.This infrared rays receiver comprises: above-mentioned current detection circuit; And the sensitive device that is connected with the detection terminal of current detection circuit.Sensitive device can be phototransistor or photodiode.According to this scheme, can detect the electric current that flows through in the sensitive device well, can carry out the mensuration of light income accurately.
Another scheme of the present invention is an electronic equipment.This electronic equipment comprises: luminescent device; The above-mentioned infrared rays receiver of the light of the light that detection is sent from luminescent device after the exterior object reflection.Luminescent device can stop luminous when reaching predetermined value by the detected catoptrical light quantity of infrared rays receiver.
Means 2.
A scheme of the present invention is to detect the current detection circuit of the electric current that flows through in the sensitive device.This current detection circuit comprises: be arranged on the 1st transistor on the current path of sensitive device; The charging capacitor that the current potential of one end has been fixed; Constitute current mirroring circuit with the 1st transistor, the electric current that flows through in the 1st transistor is become pre-determined factor times the 2nd transistor that charges to charging capacitor in the back; And the discharge switch that is arranged in parallel with charging capacitor.The discharge with switch sensitive device begun by light before the connection schedule time.
According to this scheme, before the light incident that should receive by sensitive device, make discharge use switch connection, can prevent that thus electric charge is charged in the charging capacitor, can only carry out voltage transitions by charging capacitor, can carry out correct light and detect electric current with the photophase that should receive.
Current detection circuit can also comprise the shielding switch that is set on the current path that comprises the 2nd transistor and charging capacitor.This shielding with switch can sensitive device begun by light before disconnect the schedule time.During shielding was with the switch disconnection, the current mirroring circuit that is made of the 1st transistor and the 2nd transistor disconnected, so the charge path of charging capacitor is disconnected.Of the charging of unwanted photocurrent can be prevented, and the current sinking of circuit can be reduced charging capacitor.
Can discharge with switch and shielding switching on and off based on same signal controlling with switch.Current detection circuit can also comprise makes sensitive device be subjected to light to begin the delay circuit that control signal that the front signal level changes postpones.Can make based on the output signal of this delay circuit above-mentioned discharge with switch and above-mentioned shielding with switch connection or disconnection.
Another program of the present invention is an infrared rays receiver.This infrared rays receiver comprises: sensitive device; And the above-mentioned current detection circuit of the photocurrent that flows through in the detection sensitive device.Sensitive device can be phototransistor or photodiode.
Another program of the present invention is an electronic equipment.This electronic equipment comprises: luminescent device; And the above-mentioned infrared rays receiver that detects the light of light after the exterior object reflection that sends from luminescent device.Luminescent device can stop luminous when reaching predetermined value by the detected catoptrical light quantity of infrared rays receiver.
Means 3.
An emission control device that scheme is the luminance of controlling light emitting device of the present invention.This emission control circuit comprises: infrared rays receiver, be connected with the sensitive device that receives the light of light after the exterior object reflection that sends from luminescent device, to this sensitive device in the corresponding electric current of photocurrent that flows through carry out integration, convert voltage to; Comparer compares the output voltage and the predetermined threshold value voltage of infrared rays receiver, and output becomes the comparison signal of predetermined level when output voltage is higher than threshold voltage; And latch cicuit, latch from the comparison signal of comparer output.This emission control device makes the luminescent device can not be luminous during the comparison signal of latch circuit latches predetermined level.
So-called latch cicuit is meant the circuit that D latch cicuit, RS latch cicuit, d type flip flop, rest-set flip-flop etc. can latch input signals.According to this scheme, output voltage at infrared rays receiver changes near threshold voltage, during from the comparison signal change of comparer output, because based on the signal controlling luminance that has latched comparison signal, so can prevent the situation that light-emitting device is lighted repeatedly and extinguished.
Latch cicuit can be resetted by the luminous control signal of indication luminescent device.Under these circumstances, be instructed at every turn luminous, but can both make it to return luminance.
Latch cicuit can be that the current potential of data terminal is fixed, clock terminal is transfused to from the D latch cicuit of the comparison signal of comparer output.In addition, latch cicuit can be that the current potential of data terminal is fixed, clock terminal is transfused to from the D trigger circuit of the comparison signal of comparer output.
Emission control device can also comprise the booster circuit of the driving voltage that generates luminescent device.
Emission control device can be integrated on a Semiconductor substrate.So-called " integrating ", all structure important documents that comprise circuit all are formed on the situation on the Semiconductor substrate, and the primary structure important document of circuit situation about being integrated, also can a part of resistance, electric capacity etc. be arranged on the outside of Semiconductor substrate for the regulating circuit constant.
Another program of the present invention is an electronic equipment.This electronic equipment comprises: luminescent device; And the above-mentioned emission control device of controlling the luminance of this luminescent device.According to this scheme, controlling light emitting device luminous stably and stop luminous in the electronic equipment of luminescent device is installed.
In addition, with the scheme of the combination in any of above inscape, inscape of the present invention and expression way phase double replacement between method, device, system etc., also be effective as embodiments of the present invention.
(invention effect)
By current detection circuit of the present invention, can carry out stable current detecting.In addition, by emission control device of the present invention, the luminous of luminescent device stopped.
Description of drawings
Fig. 1 is the circuit diagram of structure of the electronic equipment of expression embodiment.
Fig. 2 is the circuit diagram of structure of the infrared rays receiver of presentation graphs 1.
Fig. 3 is the circuit diagram of structure of the light emitting control portion of presentation graphs 1.
Fig. 4 is the sequential chart of operating state of the electronic equipment of presentation graphs 1.
Fig. 5 is the figure of expression as the 1st transistorized current characteristics of bipolar transistor.
Fig. 6 is the light income current detection circuit hour and the sequential chart of the operating state of electronic equipment of expression phototransistor.
Fig. 7 is the sequential chart of the action of the emission control device of expression when making luminous the stopping of luminescent device.
(label declaration)
10 primary current paths, 12 bias current paths, 20 comparers, 22 D latch cicuits, 24 single-shot trigger circuits, 26 the 1st phase inverters, 28 Sheffer stroke gates, 30 driving circuits, 32 the 2nd phase inverters, 34 delay circuits, C20 electric capacity, 100 current detection circuits, 102 detection terminals, 104 electric capacity splicing ears, 106 resistance splicing ears, 108 resistance splicing ears, 200 infrared rays receivers, 210 phototransistors, 300 electronic equipments, 302 emission control devices, 310 batteries, 320 DC/DC converters, 330 luminescent devices, 340 light emitting control portions, 350 light emitting control transistors, R10 the 1st resistance, R12 the 2nd resistance, Q1 the 1st transistor, Q2 the 2nd transistor, Rbias1 the 1st biasing resistor, Rbias2 the 2nd biasing resistor, the SW1 biased witch, the SW2 by-pass switch, SW3 shielding switch, SW4 discharge switch, Radj regulates resistance, the Cchg charging capacitor, CNT1 the 1st control signal, CNT2 the 2nd control signal, CNT3 the 3rd control signal.
Embodiment
Below, based on preferred embodiment, with reference to description of drawings the present invention.Mark identical label for inscape, parts, the processing identical or that be equal to shown in each accompanying drawing, and suitably the repetitive description thereof will be omitted.In addition, embodiment is an illustration, and non-limiting the present invention, and all features and the combination thereof recorded and narrated in the embodiment not necessarily are exactly essential characteristic of the present invention.
Fig. 1 is the figure of structure of the electronic equipment 300 of expression present embodiment.The electronic equipment 300 of present embodiment for example is the portable telephone terminal of band camera, possesses flashlamp.Electronic equipment 300 is the infrared rays receivers that possess the light that is reflected after detection is flashed, and stops the luminous equipment of flashlamp after detecting predetermined light quantity.
After the user opened flashlamp, the control signal CNT that synchronously becomes high level with the sequential of shutter was imported into light emitting control portion 340.Light emitting control portion 340 switches to high level based on control signal CNT with led control signal SIG1 as described later like that.Led control signal SIG1 becomes behind the high level through after the delay time T, 350 conductings of light emitting control transistor, and luminescent device 330 is luminous.Delay time T is by the characteristic decision of xenon spot.
In addition, light emitting control portion 340 generates the 1st control signal CNT1～the 3rd control signal CNT3 based on control signal CNT, outputs to infrared rays receiver 200.Infrared rays receiver 200 changes the stand-by state that is used to be subjected to light into according to the 1st control signal CNT1～the 3rd control signal CNT3 from 340 outputs of light emitting control portion.Afterwards, infrared rays receiver 200 detects the light that reflects from the reference object thing that luminescent device 330 sends and quilt is outside, as detecting voltage Vdet output.Light emitting control portion 340 makes led control signal SIG1 become low level when detecting voltage Vdet and surpass predetermined threshold value voltage Vth, when detected reflected light reaches predetermined light quantity, stops the luminous of luminescent device 330.
Next, describe the structure of the infrared rays receiver 200 of present embodiment in detail.Fig. 2 is the circuit diagram of structure of the infrared rays receiver 200 of expression present embodiment.Infrared rays receiver 200 comprises current detection circuit 100, phototransistor 210, charging capacitor Cchg, regulates resistance R adj.Current detection circuit 100 is integrated the IC on a Semiconductor substrate, and in the present embodiment, the light emitting control portion 340 of Fig. 1, the control circuit of DC/DC converter 320 etc. is all integrated as function IC.
The photocurrent Ip that flows through in the phototransistor 210 that current detection circuit 100 detects with detection terminal 102 is connected.Current detection circuit 100 comprises the 1st transistor Q1, the 2nd transistor Q2, the 1st biasing resistor Rbias1, the 2nd biasing resistor Rbias2, biased witch SW1, by-pass switch SW2, the 1st resistance R the 10, the 2nd resistance R 12.In addition,, between resistance splicing ear 106 and resistance splicing ear 108, connect and regulate resistance R adj, on electric capacity splicing ear 104, connect charging capacitor Cchg in the outside of current detection circuit 100.
The 1st transistor Q1 is positive-negative-positive bipolar transistor (being designated hereinafter simply as the PNP transistor), is set on the current path as the phototransistor 210 of sensitive device.At the emitter-base bandgap grading of the 1st transistor Q1 be applied between the power lead of supply voltage Vdd, connect the 1st resistance R 10.In addition, link to each other between base-collection of the 1st transistor Q1.
The 2nd transistor Q2 is the PNP transistor, interconnects with the 1st transistor Q1 base stage.Between the emitter-base bandgap grading of the 2nd transistor Q2 and power lead, be provided with the 2nd resistance R 12.And be connected adjusting resistance R adj in parallel with the 2nd resistance R 12.The 2nd transistor Q2 constitutes current mirror (current mirror) circuit with the 1st transistor Q1, the 1st resistance R the 10, the 2nd resistance R 12, adjusting resistance R adj.The 2nd transistor Q2 output becomes the 2nd electric current I q2 of pre-determined factor after doubly with the 1st electric current I q1 that flows through among the 1st transistor Q1.For example, the 1st transistor Q1 is set at about 4: 1 with the size ratio of the 2nd transistor Q2.
Will be from the collector of the 1st transistor Q1, via detection terminal 102, phototransistor 210 to the path of ground connection as primary current path 10.Between the 1st transistor Q1 of primary current path 10 and detection terminal 1 02, be provided with the 2nd biasing resistor Rbias2.The resistance value of the 2nd biasing resistor Rbias2 is set enough highly, for example sets in the scope of number M Ω～tens of M Ω.In the present embodiment, as an example, be set at 10M Ω.Primary current path 10 also has the by-pass switch SW2 with the 2nd biasing resistor Rbias2 bypass.By-pass switch SW2 is switched on and off by the 1st control signal CNT1 control from 340 outputs of light emitting control portion.
Be arranged in parallel bias current path 12 with primary current path 10.Bias current path 12 comprises the collector that is connected in series in the 1st transistor Q1 and the 1st biasing resistor Rbias1 and the biased witch SW1 between ground connection.The resistance value of the 1st biasing resistor Rbias1 is enough low with respect to the 2nd biasing resistor Rbias2, for example be set at its about 1/10.The resistance value of the 2nd biasing resistor Rbias2 for example is 1M Ω.
Control switching on and off of biased witch SW1 by the 3rd control signal CNT3 that generates by light emitting control portion 340.When biased witch SW1 connected, bias current path 12 was connected, and flows through electric current.Below, the electric current that will flow through bias current path 12 is called bias current Ibias.
The collector of the 2nd transistor Q2 is connected with electric capacity splicing ear 1 04 with switch SW 3 via shielding (mask).Current detection circuit 100 makes the 2nd electric current I q2 that flows through among the 2nd transistor Q2 be charged to charging capacitor Cchg, is transformed into voltage.Shielding switches on and off by the 2nd control signal CNT2 control that generates in light emitting control portion 340 with switch SW 3.Shielding disconnects during for high level at the 2nd control signal CNT2 with switch SW 3, connects during for low level at the 2nd control signal CNT2.After shielding disconnects with switch SW 3, owing to being opened circuit in the path of the 2nd electric current I q2, so the charging of charging capacitor Cchg stops.
Between electric capacity splicing ear 104 and ground connection, be provided with discharge switch SW 4.Discharge is nmos pass transistors with switch SW 4, and Cchg is connected in parallel with charging capacitor.Discharge is connected with electric capacity splicing ear 104 with the drain electrode of switch SW 4, and source ground, grid are transfused to the 2nd control signal CNT2 that is generated by light emitting control portion 340.Discharge is connected during for high level at the 2nd control signal CNT2 with switch SW 4, disconnects during for low level at the 2nd control signal CNT2.After discharge was connected with switch SW 4, electric capacity splicing ear 104 was grounded, and is accumulated in the charge discharge among the charging capacitor Cchg.As described later, discharge is connected schedule time Δ T1 based on the 2nd control signal CNT2 with switch SW 4 before phototransistor 210 is begun by light.Discharge, is controlled by same the 2nd control signal CNT2 with the switching on and off of switch SW 3 with switch SW 4 and shielding.
The current detection circuit 100 of present embodiment is exported to light emitting control portion 340 with the voltage that presents on the electric capacity splicing ear 104 as detecting voltage Vdet.
Next, the structure of light emitting control portion 340 is described.Fig. 3 is the circuit diagram of structure of the light emitting control portion 340 of expression present embodiment.Light emitting control portion 340 comprises comparer 20, D latch cicuit 22, single-shot trigger circuit the 24, the 1st phase inverter 26, Sheffer stroke gate 28, driving circuit the 30, the 2nd phase inverter 32, delay circuit 34.
Light emitting control portion 340 based on be input to control terminal 342, phototransistor 210 is subjected to light to begin the control signal CNT that the front signal level changes, and generates the 1st control signal CNT1～the 3rd control signal CNT3, exports to current detection circuit 100.In addition, light emitting control portion 340 generates led control signal SIG1 based on control signal CNT with from the detection voltage Vdet of current detection circuit 100 output, controlling light emitting device 330 luminous and stop luminous.
At first, the structural frames that generates the 1st control signal CNT1～the 3rd control signal CNT3 in light emitting control portion 340 is described.
The control signal CNT that is input to control terminal 342 exports to current detection circuit 100 as the 1st control signal CNT1 at this point.
By resistance R 20, R22, transistor Q1, the 1st phase inverter the 26, the 2nd phase inverter 32, delay circuit 34, control signal CNT is postponed, generate the 2nd control signal CNT2 thus.Transistor Q1 is the bipolar npn transistor npn npn, and emitter grounding is provided with resistance R 22 between collector and power lead.Between the base stage of transistor Q1 and control terminal 342, be connected with resistance R 20.
The output signal SIG10 of the 1st phase inverter 26 is imported into the 2nd phase inverter 32.The 2nd phase inverter 32 makes the output signal SIG10 logic inversion of the 1st phase inverter 26, exports to delay circuit 34.Delay circuit 34 makes the output signal delay scheduled time Δ T1 of the 2nd phase inverter 32.Be output to current detection circuit 100 from the signal of delay circuit 34 outputs as the 2nd control signal CNT2.For example, Δ T1 time delay of delay circuit 34 is set at about 5 μ s.
Be subjected to light to begin the control signal CNT that the front signal level changes at phototransistor 210 and be imported into single-shot trigger circuit 24.Single-shot trigger circuit 24 is the 3rd control signal CNT3 of high level in being created on during the schedule time Δ T2 after control signal CNT becomes high level.That is, single-shot trigger circuit 24 is the latch cicuits that control signal CNT latched schedule time Δ T2.The 3rd control signal CNT3 is exported to biased witch SW1, controls it and switches on and off.Schedule time Δ T2 for example is set at about 10 μ s than Δ T1 length time delay.
The light emitting control portion 340 that constitutes as described above generates the 1st control signal CNT1～the 3rd control signal CNT3, exports to current detection circuit 100.
Next, the structural frames that generates the luminous led control signal SIG1 that is used for controlling light emitting device 330 in light emitting control portion 340 is described.This structural frames comprises comparer 20, D latch cicuit 22, Sheffer stroke gate 28, driving circuit 30.
Be imported into the clock terminal of D latch cicuit 22 from the comparison signal SIG12 of comparer 20 outputs.The data terminal of D latch cicuit 22 is connected in power lead, is fixed to high level.The reseting terminal of D latch cicuit 22 is transfused to control signal CNT.D latch cicuit 22 is as coming work by the rising edge set of comparison signal SIG12, the latch cicuit that resetted by the negative edge of control signal CNT.The counter-rotating output signal SIG14 of D latch cicuit 22 is output to Sheffer stroke gate 28.
The negative logic of the output signal SIG10 of Sheffer stroke gate 28 outputs the 1st phase inverter 26 and the counter-rotating output signal SIG14 of D latch cicuit 22 is long-pending.Signal level was the led control signal SIG1 of high level in driving circuit 30 was exported during the output signal of Sheffer stroke gate 28 is low level.
The following describes the action of the light emitting control portion 340 of the current detection circuit 100 of the Fig. 2 that as above constitutes like that and Fig. 3.Fig. 4 is the sequential chart of the operating state of expression current detection circuit 100 of present embodiment and electronic equipment 300.
Before moment T0, supply voltage Vdd starting, current detection circuit 100 becomes holding state.During this, there is very little photocurrent Ip (dark current) to flow through in the phototransistor 210.This photocurrent Ip flows through as the 1st electric current I q1 in the 1st transistor Q1.Because the 1st transistor Q1 is connection between base-collection, thus collect-penetrate a voltage Vce equal basic-penetrate a voltage Vbe.The current potential Vptr of detection terminal 102 presents the voltage (Vdd-Vce-Δ Vr) than the voltage drop Δ Vr on the collection of low the 1st transistor Q1 of supply voltage Vdd-penetrate a voltage Vce (=base-penetrate a voltage Vbe) and the 1st resistance R 10.Because the photocurrent Ip that flows through in the phototransistor 210 is less, so the collection of the 1st transistor Q1-penetrate a voltage Vce is less.
At moment T0, control signal CNT becomes high level, and indication luminescent device 330 carries out luminous.As mentioned above, when control signal CNT became high level, the 1st control signal CNT1 became high level.In addition, the 3rd control signal CNT3 from single-shot trigger circuit 24 outputs is becoming high level in the schedule time Δ T2 of moment T1.
At moment T0, after the 1st control signal CNT1 became high level, by-pass switch SW2 connected, and the 2nd biasing resistor Rbias2 is by bypass.In addition, after the 3rd control signal CNT3 became high level, biased witch SW1 connected, and flows through bias current Ibias in the bias current path 12.
At this moment, the electric current I q1 that flows through among the 1st transistor Q1 become photocurrent Ip and bias current Ibias and (Ip+Ibias).As mentioned above, because the resistance value of the 1st biasing resistor Rbias1 is set enough lowly with respect to the resistance value of the 2nd biasing resistor Rbias2, so the 1st electric current I q1 that flows through among the 1st transistor Q1 increases.Compare during before its result, the collection of the 1st transistor Q1-penetrate a voltage Vce and moment T0 and become big, the current potential Vptr of detection terminal 102 reduces.
Be subjected to the moment T0 of light before beginning at luminescent device 330, connect by-pass switch SW2, flow through bias current Ibias in the bias current path 12, thus, the 1st electric current I q1 increases.The 1st electric current I q1 increases, and means that the collector current Ice of the 1st transistor Q1 increases.
Fig. 5 is the figure of expression as the current characteristics of the 1st transistor Q1 of bipolar transistor.The longitudinal axis of this figure represent collector current Ice (=Iq1), transverse axis represents to collect-penetrate a voltage Vce (=base-penetrate a voltage Vbe).As shown in Figure 5, collector current Ice (=Iq1) hour, bigger with respect to the collection of the change of collector current Ice-the penetrate amplitude of fluctuation of voltage Vce, when collector current Ice became big, this amplitude of fluctuation diminished.
Therefore, as before the moment T0 like that, the 1st electric current I q1 (collector current Ice) hour, the 1st electric current I q1 is subtle change only, the voltage Vptr of the collector voltage of the 1st transistor Q1 and then detection terminal 102 just changes.The voltage Vptr change of detection terminal 102, then the bias state of phototransistor 210 changes, and photocurrent Ip just might change.In addition, because the voltage change of detection terminal 102 comprises that the characteristic of the current mirroring circuit of the 1st transistor Q1, the 2nd transistor Q2 worsens sometimes.
Therefore, in the current detection circuit 100 of present embodiment, the moment T0 before begun by light connects biased witch SW1, and the 1st electric current I q1 is increased.Its result, the 1st transistor Q1 is biased in the constant current region, with respect to the collection of the variable quantity of collector current Ice-penetrate the variable quantity of voltage Vce to diminish, can make the voltage Vptr of detection terminal 102 keep constant.The voltage Vptr of detection terminal 102 be held constant after, can make the characteristic of phototransistor 210 keep constant, and can make the characteristic of the current mirroring circuit that comprises the 1st transistor Q1, the 2nd transistor Q2 keep good.
In addition, the 2nd control signal CNT2 changes the moment T0 of high level from control signal CNT into from low level, only is latched to the moment T1 that passes through behind the schedule time Δ T1, keeps high level.At the 2nd control signal CNT2 is between high period, and discharge is connected with switch SW 4, so the electric charge that is accumulated among the charging capacitor Cchg is discharged, is carried out initialization.And then, be between high period at the 2nd control signal CNT2, shielding disconnects with switch SW 3, so opened circuit in the path of the 2nd electric current I q2.Its result, before moment T1, even light incides luminescent device 330, photocurrent Ip flows through, and charging capacitor Cchg is not recharged yet, and detects voltage Vdet and is fixed to earthing potential.In addition, owing to circuital current is opened circuit, so can seek the low consumption electrification.
At moment T0, led control signal SIG1 becomes high level, but luminescent device 330 becomes luminance.The luminescent device 330 of present embodiment delay time T after led control signal SIG1 becomes high level is carried out luminous.Therefore, above-mentioned schedule time Δ T1 need set shortlyer than time τ.
At moment T1, after the 2nd control signal CNT2 became low level, shielding was connected with switch SW 3, and discharge disconnects with switch SW 4, and current detection circuit 100 becomes stand-by state.
Moment T2 behind the moment T0 elapsed time τ that becomes high level from led control signal SIG1, luminescent device 330 is luminous.After luminescent device 330 was luminous, reflected light incided phototransistor 210, and photocurrent Ip flows through.At moment T2, owing to bias current path 12 disconnects, so the 1st electric current I q1 that flows through among the 1st transistor Q1 equates with photocurrent Ip.As mentioned above, because the 1st transistor Q1 is biased in constant current region, so even photocurrent Ip begins to flow through, the current potential Vptr of detection terminal 102 is change hardly also.
After moment T2, charging capacitor Cchg is detected voltage Vdet and slowly rises by the 2nd electric current I q2 charging from the 2nd transistor Q2 output.At moment T3, after detection voltage Vdet reached predetermined threshold value voltage Vth, the comparison signal SIG12 of the output of device 20 became high level as a comparison, and the counter-rotating output signal SIG14 of D latch cicuit 22 becomes low level.Its result, the led control signal SIG1 that exports from driving circuit 30 becomes low level, and light emitting control transistor 350 ends, and the luminous of luminescent device 330 stops.
Afterwards, at the moment T4 behind moment T0 process schedule time Δ T2, the 3rd control signal CNT3 becomes low level, and biased witch SW1 disconnects.
In addition, by the 2nd biasing resistor Rbias2 is set, the impedance of primary current path 10 is improved during can be before begun by light, can reduce the current sinking of circuit.
Fig. 6 is the light income current detection circuit 100 hour and the sequential chart of the operating state of electronic equipment 300 of expression phototransistor 210.
At the moment T3 behind moment T0 process schedule time Δ T2, the 3rd control signal CNT3 becomes low level.After the 3rd control signal CNT3 became low level, biased witch SW1 disconnected, and bias current path 12 disconnects.After moment T4, biased witch SW1 does not flow through bias current Ibias after disconnecting, and equals photocurrent Ip so the 1st electric current I q1 that flows through among the 1st transistor Q1 becomes.Its result, to the charging current minimizing of charging capacitor Chg, the ascending velocity that detects voltage Vdet descends.
Afterwards, at moment T5, after detection voltage Vdet reached threshold voltage vt h, led control signal SIG1 became low level, and the luminous of luminescent device 330 stops.
Thereby, the infrared rays receiver 200 of present embodiment and light emitting control portion 340 disconnect biased witch SW1 through the schedule time (Δ T2-τ) back, set the 1st electric current I q1 to such an extent that equate thus with photocurrent Ip, thereby can correctly detect the light income of phototransistor 210, can be controlled to the time of closing luminescent device 330 rightly.
In addition, at moment T4, flow through photocurrent Ip among the 1st transistor Q1, so even turn-off bias current Ibias, the bias state of the 1st transistor Q1 does not drop to non-constant galvanic areas yet, the current potential Vptr of detection terminal 102 does not significantly change.
And then, according to the infrared rays receiver 200 and the light emitting control portion 340 of present embodiment,, have following effect by discharge being set with switch SW 4 and shielding switch SW 3.
Behind current detection circuit 100 supply line voltages, because phototransistor 210 is biased, so might flow through dark current, perhaps because of not being subjected to the light of light to flow through photocurrent Ip from the original of outside incident, charging capacitor Cchg is recharged.Therefore, by before phototransistor 210 is begun by light, make discharge connect the scheduled period with switch SW 4, can prevent to make charging capacitor Cchg charging by unwanted electric current, and can make the charge discharge that is accumulated among the charging capacitor Cchg, will detect voltage Vdet and be set at initial value.And then, by before phototransistor 210 is begun by light, disconnecting shielding, can prevent to make charging capacitor Cchg charging, and can reduce the current sinking of circuit by the 2nd electric current I q2 with switch SW 3.
And then, by latching with D latch cicuit 22 from the comparison signal SIG12 of comparer 20 outputs, can prevent that when detecting voltage Vdet and near threshold voltage vt h, change led control signal SIG1 is in the situation that high level and low level, luminescent device 330 are in luminance and luminous halted state repeatedly repeatedly.
Fig. 7 is that the luminescent device 330 that makes of the emission control device 302 of expression present embodiment stops the sequential chart of the action when luminous.Become at control signal CNT before the moment T10 of high level, D latch cicuit 22 is reset, and counter-rotating output signal SIG14 becomes high level.At this moment, the output signal SIG16 of Sheffer stroke gate 28 is high level, and led control signal SIG1 becomes low level.
When moment T10 control signal CNT became high level, the output signal SIG16 of Sheffer stroke gate 28 became low level, and led control signal SIG1 becomes high level, 350 conductings of light emitting control transistor.Soon afterwards, luminescent device 330 is luminous.
After luminescent device 330 is luminous, begin to rise from the detection voltage Vdet of infrared rays receiver 200 outputs.After moment T11 detection voltage Vdet reached threshold voltage vt h, the comparison signal SIG12 that exports from comparer 20 became high level, and the counter-rotating output signal SIG14 of D latch cicuit 22 becomes low level.
After the counter-rotating output signal SIG14 of D latch cicuit 22 became low level, the output signal SIG16 of Sheffer stroke gate 28 became high level, and led control signal SIG1 becomes low level, and light emitting control transistor 350 ends, and the luminous of luminescent device 330 stops.
The counter-rotating output signal SIG14 of D latch cicuit 22, during comparison signal SIG12 being latched that back to the negative edge of controlled signal CNT next resets from moment T11 in, continue to keep low level.Its result, even detect voltage Vdet change, comparison signal SIG12 has changed, and luminous the continuing of luminescent device 330 stopped.
After moment T12 control signal CNT changed low level into from high level, D latch cicuit 22 was reset, and counter-rotating output signal SIG14 becomes high level.During from moment T12 to moment T13, led control signal SIG1 is a low level.In addition, from moment T12 through the moment T13 behind the schedule time Δ T1, become high level as the 2nd control signal CNT2 of the output signal of delay circuit 34.After the 2nd control signal CNT2 became high level, discharge was connected with switch SW 4, detected voltage Vdet and was initialized to earthing potential.Then, CNT becomes high level in moment T14 control signal, indicates luminous next time.
Like this, emission control device 302 according to present embodiment, by latching with D latch cicuit 22 from the comparison signal SIG12 of comparer 20 outputs, can prevent that led control signal SIG1 is in high level repeatedly and low level, luminescent device 330 are in luminance and luminous halted state repeatedly when detection voltage Vdet changes near threshold voltage vt h.
In addition, by the D latch cicuit 22 that resets of the negative edge with control signal CNT, before can being transfused to once more at rising edge, but turn back to luminance corresponding to the control signal CNT of luminous indication.
Above-mentioned embodiment is an illustration, can carry out various distortion to the combination of each inscape and variety of processes, and those skilled in the art can understand these variation and also be in the scope of the present invention.
In embodiment, be to constitute bias current path 12, but be not limited thereto by the 1st biasing resistor Rbias1 and the biased witch SW1 that is connected in series, also can use the constant current supply that generates predetermined current.At this moment, by the open and close constant current supply, the bias state of the 1st transistor Q1 is changed.
In embodiment, be to latch from the comparison signal SIG12 of comparer 20 output, but be not limited thereto with D latch cicuit 22, also can use d type flip flop.In addition, also can use the rest-set flip-flop that resets by comparison signal SIG12 set, by the negative edge of control signal CNT.Use any one, can both obtain effect identical when using D latch cicuit 22.
In embodiment, be to constitute bias current path 12, but be not limited thereto by the 1st biasing resistor Rbias1 and the biased witch SW1 that is connected in series, also can use the constant current supply that generates predetermined current.At this moment, by the open and close constant current supply, the bias state of the 1st transistor Q1 is changed.
In embodiment, be to use phototransistor 210 as sensitive device, but also can use photodiode to replace it.
In embodiment, replaceable each other with the original paper that MOSFET, bipolar transistor constitute.These selections decide and get final product according to semiconductor fabrication process, cost, the desired use of circuit.Further, supply voltage and earthing potential being put upside down, also is effective with the displacement of PNP transistor and NPN transistor or with the circuit structure after PMOS transistor and the nmos pass transistor displacement.
In embodiment, the situation that infrared rays receiver 200 and light emitting control portion 340 are integrated has been described, but also can has been that a part is made of discrete parts.Integrated as for which is partly carried out, get final product according to decisions such as cost, area occupied, purposes.
Describe the present invention based on embodiment, but embodiment only is expression principle of the present invention, application, in the scope of the thought of the present invention that does not break away from claims defined, can carries out a lot of variation and change configuration embodiment.
(industrial utilizability)
The present invention can be applicable to the electrical equipment that luminescent device or sensitive device are installed.
Claims (30)
1. the current detection circuit of the electric current that flows through in a detection and the sensitive device that detection terminal is connected is characterized in that, comprising:
Be arranged on the 1st transistor on the current path of above-mentioned sensitive device;
Be arranged in parallel the bias current path of the control that can switch on and off with the primary current path that comprises above-mentioned sensitive device; And
Constitute current mirroring circuit with above-mentioned the 1st transistor, the electric current that flows through in above-mentioned the 1st transistor is become 2nd transistor of pre-determined factor times back as the output of this current detection circuit;
Wherein, above-mentioned bias current path begins preceding connection at the light that is subjected to of above-mentioned sensitive device.
2. current detection circuit according to claim 1 is characterized in that:
Above-mentioned bias current path is beginning to be subjected to light to disconnect through after the schedule time from above-mentioned sensitive device.
3. current detection circuit according to claim 2 is characterized in that:
Also comprise the light that is subjected at sensitive device is begun the latch cicuit that control signal that the front signal level changes latchs the schedule time,
With the output signal of this latch cicuit as the signal that switches on and off that is used to control above-mentioned bias current path.
4. according to each described current detection circuit of claim 1 to 3, it is characterized in that:
Above-mentioned bias current path comprises the 1st biasing resistor and the biased witch that is connected in series.
5. according to each described current detection circuit of claim 1 to 3, it is characterized in that:
Also be included in the 2nd set biasing resistor between above-mentioned the 1st transistor on the above-mentioned primary current path and the above-mentioned detection terminal.
6. current detection circuit according to claim 5 is characterized in that:
Also comprise the by-pass switch with above-mentioned the 2nd biasing resistor bypass, above-mentioned by-pass switch begins preceding connection at the light that is subjected to of above-mentioned sensitive device.
7. according to each described current detection circuit of claim 1 to 3, it is characterized in that:
Above-mentioned current detection circuit makes the electric current that flows through in above-mentioned the 2nd transistor charge to electric capacity, converts voltage to and exports.
8. according to each described current detection circuit of claim 1 to 3, it is characterized in that:
Integrated on a Semiconductor substrate.
9. an infrared rays receiver is characterized in that, comprising:
The described current detection circuit of each of claim 1 to 3; And
The sensitive device that is connected with the above-mentioned detection terminal of above-mentioned current detection circuit.
10. infrared rays receiver according to claim 9 is characterized in that:
Above-mentioned sensitive device is a phototransistor.
11. infrared rays receiver according to claim 9 is characterized in that:
Above-mentioned sensitive device is a photodiode.
12. an electronic equipment is characterized in that, comprising:
Luminescent device; And
The described infrared rays receiver of claim 9 of the light of the light that detection is sent from above-mentioned luminescent device after the exterior object reflection.
13. electronic equipment according to claim 12 is characterized in that:
Above-mentioned luminescent device stops luminous when reaching predetermined value by the detected catoptrical light quantity of above-mentioned infrared rays receiver.
14. a current detection circuit that detects the electric current that flows through in the sensitive device is characterized in that, comprising:
Be arranged on the 1st transistor on the current path of above-mentioned sensitive device;
The charging capacitor that the current potential of one end has been fixed;
Constitute current mirroring circuit with above-mentioned the 1st transistor, the electric current that flows through in above-mentioned the 1st transistor is become pre-determined factor doubly, and the 2nd transistor that above-mentioned charging capacitor is charged; And
The discharge switch that is arranged in parallel with above-mentioned charging capacitor;
Wherein, above-mentioned discharge with switch above-mentioned sensitive device begun by light before connect the schedule time.
15. current detection circuit according to claim 14 is characterized in that:
Also comprise the shielding switch that is set on the current path that comprises above-mentioned the 2nd transistor and above-mentioned charging capacitor, above-mentioned shielding with switch above-mentioned sensitive device begun by light before disconnect the schedule time.
16. current detection circuit according to claim 15 is characterized in that:
Based on the above-mentioned discharge of same signal controlling with switch and above-mentioned shielding switching on and off with switch.
17. current detection circuit according to claim 16 is characterized in that:
Also comprise making being subjected to light to begin the delay circuit that control signal that the front signal level changes postpones at sensitive device,
With the output signal of this delay circuit as being used to control above-mentioned discharge with switch and above-mentioned shielding the signal that switches on and off with switch.
18. each the described current detection circuit according to claim 14 to 17 is characterized in that:
Integrated on a Semiconductor substrate.
19. an infrared rays receiver is characterized in that, comprising:
Sensitive device; And
Detect each described current detection circuit of the claim 14 to 17 of the photocurrent that flows through in the above-mentioned sensitive device.
20. infrared rays receiver according to claim 19 is characterized in that:
Above-mentioned sensitive device is a phototransistor.
21. infrared rays receiver according to claim 19 is characterized in that:
Above-mentioned sensitive device is a photodiode.
22. an electronic equipment is characterized in that, comprising:
Luminescent device; And
The described infrared rays receiver of claim 19 of the light of the light that detection is sent from above-mentioned luminescent device after the exterior object reflection.
23. electronic equipment according to claim 22 is characterized in that:
Above-mentioned luminescent device stops luminous when reaching predetermined value by the detected catoptrical light quantity of above-mentioned infrared rays receiver.
24. the emission control device of the luminance of a controlling light emitting device is characterized in that, comprising:
Infrared rays receiver is connected with the sensitive device that receives the light of light after the exterior object reflection that sends from above-mentioned luminescent device, to this sensitive device in the corresponding electric current of photocurrent that flows through carry out integration, convert voltage to;
Comparer compares the output voltage and the predetermined threshold value voltage of above-mentioned infrared rays receiver, and output becomes the comparison signal of predetermined level when above-mentioned output voltage is higher than above-mentioned threshold voltage; And
Latch cicuit latchs from the comparison signal of above-mentioned comparer output;
Wherein, during the comparison signal of the above-mentioned predetermined level of above-mentioned latch circuit latches, make the above-mentioned luminescent device can not be luminous.
25. emission control device according to claim 24 is characterized in that:
Above-mentioned latch cicuit is resetted by the luminous control signal of the above-mentioned luminescent device of indication.
26. emission control device according to claim 24 is characterized in that:
Above-mentioned latch cicuit is that the current potential of data terminal is fixed, clock terminal is transfused to from the D latch cicuit of the comparison signal of above-mentioned comparer output.
27. emission control device according to claim 24 is characterized in that:
Above-mentioned latch cicuit is that the current potential of data terminal is fixed, clock terminal is transfused to from the D trigger circuit of the comparison signal of above-mentioned comparer output.
28. each the described emission control device according to claim 24 to 27 is characterized in that:
Above-mentioned emission control device also comprises the booster circuit of the driving voltage that generates above-mentioned luminescent device.
29. each the described emission control device according to claim 24 to 27 is characterized in that:
Integrated on a Semiconductor substrate.
30. an electronic equipment is characterized in that, comprising:
Luminescent device; And
Control each described emission control device of claim 24 to 27 of the luminance of above-mentioned luminescent device.
Applications Claiming Priority (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005296721A JP5068011B2 (en) | 2005-10-11 | 2005-10-11 | CURRENT DETECTION CIRCUIT, LIGHT RECEIVER AND ELECTRONIC DEVICE USING THE SAME |
| JP2005296963A JP5068012B2 (en) | 2005-10-11 | 2005-10-11 | LIGHT EMITTING CONTROL DEVICE AND ELECTRONIC DEVICE USING THE SAME |
| JP296719/2005 | 2005-10-11 | ||
| JP296963/2005 | 2005-10-11 | ||
| JP2005296719A JP5015442B2 (en) | 2005-10-11 | 2005-10-11 | CURRENT DETECTION CIRCUIT, LIGHT RECEIVER AND ELECTRONIC DEVICE USING THE SAME |
| JP296721/2005 | 2005-10-11 | ||
| PCT/JP2006/318288 WO2007043282A1 (en) | 2005-10-11 | 2006-09-14 | Current detection circuit, photoreceiver using the same, light emission control device, and electronic device using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101099079A true CN101099079A (en) | 2008-01-02 |
| CN101099079B CN101099079B (en) | 2011-09-21 |
Family
ID=38033910
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2006800017650A Expired - Fee Related CN101099079B (en) | 2005-10-11 | 2006-09-14 | Current detection circuit, photoreceiver using the same, light emission control device, and electronic device using the same |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP5015442B2 (en) |
| CN (1) | CN101099079B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103033517A (en) * | 2011-07-15 | 2013-04-10 | 株式会社Npc | Defect inspection device for solar cells and inspection method |
| CN107817011A (en) * | 2016-09-12 | 2018-03-20 | 株式会社三丰 | Photoelectric encoder |
| CN107923796A (en) * | 2015-09-02 | 2018-04-17 | 柯尼卡美能达株式会社 | Colour meter |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109842401B (en) * | 2017-11-24 | 2023-07-04 | 龙芯中科技术股份有限公司 | Latch-up resistant device and CMOS chip |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS596549B2 (en) * | 1979-07-03 | 1984-02-13 | 日本電信電話株式会社 | 3-terminal power supply circuit for telephones |
| JP4368456B2 (en) * | 1999-06-02 | 2009-11-18 | パナソニック フォト・ライティング 株式会社 | Strobe device |
| JP2001245212A (en) * | 2000-02-28 | 2001-09-07 | Mitsubishi Electric Corp | Photoelectric converter |
| JP4076805B2 (en) * | 2002-07-10 | 2008-04-16 | シャープ株式会社 | Current mirror circuit and optical signal circuit using the same |
| JP4295075B2 (en) * | 2003-12-05 | 2009-07-15 | 日本電信電話株式会社 | Photoelectric conversion circuit and electric field detection optical device |
-
2005
- 2005-10-11 JP JP2005296719A patent/JP5015442B2/en not_active Expired - Fee Related
-
2006
- 2006-09-14 CN CN2006800017650A patent/CN101099079B/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103033517A (en) * | 2011-07-15 | 2013-04-10 | 株式会社Npc | Defect inspection device for solar cells and inspection method |
| CN107923796A (en) * | 2015-09-02 | 2018-04-17 | 柯尼卡美能达株式会社 | Colour meter |
| CN107817011A (en) * | 2016-09-12 | 2018-03-20 | 株式会社三丰 | Photoelectric encoder |
| CN107817011B (en) * | 2016-09-12 | 2023-04-18 | 株式会社三丰 | Photoelectric encoder |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2007107925A (en) | 2007-04-26 |
| CN101099079B (en) | 2011-09-21 |
| JP5015442B2 (en) | 2012-08-29 |
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