CN1282960C - Automatic power controller - Google Patents
Automatic power controller Download PDFInfo
- Publication number
- CN1282960C CN1282960C CN 03109395 CN03109395A CN1282960C CN 1282960 C CN1282960 C CN 1282960C CN 03109395 CN03109395 CN 03109395 CN 03109395 A CN03109395 A CN 03109395A CN 1282960 C CN1282960 C CN 1282960C
- Authority
- CN
- China
- Prior art keywords
- signal
- power controller
- output
- automatic power
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Amplifiers (AREA)
Abstract
The present invention relates to an automatic power controller which automatically controls the output power of an optical head to reach a stable state rapidly. The automatic power controller comprises a detector, a comparator, a signal source, a gain amplifier which can be converted, and a drive unit, wherein the detector detects the output power of an optical head and generates a detection signal; the comparator compares a detection signal with a reference signal and outputs a comparison signal; the signal source provides reference signals of different voltage, and the reference signals are used as references for generating different output power; the gain amplifier which can be converted receives the comparison signal and processes the comparison signal by different gains for the reference signals of different voltage; moreover, the gain amplifier generates an output signal; the drive unit receives the output signal and generates a drive signal to drive the optical head. The comparison signals output by the comparator and the voltage difference of the corresponding reference signals are the same in different power states of the automatic power controller, so the time for charging and discharging a capacitor in the comparator is unnecessary. The time for reaching a stable state of the automatic power controller can be shortened.
Description
Technical field
The invention relates to the automatic power controller of the optical head of laser disc drive unit, particularly about utilizing different gains to make the automatic power controller of the optical head of the stable laser disc drive unit of output power rapidly.
Background of invention
Fig. 1 shows the Organization Chart of automatic power controller of the optical head of first kind of known laser disc drive unit.As shown in the drawing, known automatic power controller 10 comprises a signal source 11, a comparer 12, a driver element 13, a detector 14 and a LASER Light Source (Laser head) 15.After driver element 13 received the output signal V2 of comparer 12, driving laser light source 15 produced the laser beam of desirable strength.The brightness of 14 detectings of detector LASER Light Source 15 produces voltage signal V3 simultaneously.In this framework, comparer 12 comprises an operational amplifier 121, resistance R 1, R2 and capacitor C.This voltage signal V3 is connected to the negative terminal of operational amplifier 121 via resistance R 1, and the reference signal V1 that synchronous signal source 11 is exported is connected to the anode of operational amplifier 121.The negative terminal of operational amplifier 121 is connected to output terminal via parallel resistor R2 and capacitor C.The Organization Chart of the automatic power controller 10 of Fig. 1 only is a basic framework, can dispose another amplifier during actual design between comparer 12 and driver element 13; Or between detector 14 and comparer 12, dispose another amplifier.Detector 14 can be a front end monitoring diode (Front Monitor Diode, FMD).
When automatic power controller 10 will be varied to Pb by Pa with the output power of driver element 13, signal source 11 can be changed to V1B by V1A with reference signal.
When the reference signal of Fig. 2 A to 2D display source signal 11 becomes V1b by V1a, the wave form varies of the output signal V2 of the output signal V3 of detector 14, operational amplifier 121 and the voltage Vc of capacitor C.The output signal V2 that the wave form varies, Fig. 2 B that the reference signal of Fig. 2 A display source signal 11 is changed to V1b by V1a shows operational amplifier 121 is changed to voltage Vc that the wave form varies of V2c and V2b, output signal V3 that Fig. 2 C shows detector 14 be changed to the wave form varies of V3c and V3b and Fig. 2 D demonstration capacitor C by V3a is changed to VCb by VCa wave form varies by V2a.Because comparer 12 comprises capacitor C and under the different capacity state, the voltage difference difference at capacitor C two ends, so the output signal V2 of operational amplifier 121 must capacitor C discharge and recharge stable after, just can reach steady state (SS).And, for not being subject to noise (noise), do not disturb the output signal V2 that makes operational amplifier 121, the RC time constant of operational amplifier 121 (RC constant) can design bigger, make automatic power controller 10 need the long time to stablize, its frequency range (bandwidth) is approximately 10-20Hz.Such situation is for example sought the rail error signal and is broken away from range of control through the servocontrol error (servo fail) that regular meeting causes the laser disc drive unit.
Fig. 3 shows the Organization Chart of automatic power controller of the optical head of second kind of known laser disc drive unit.As shown in the drawing, this automatic power controller 30 also comprises one first signal source 31, a control module 33 and two switch SW 1, SW2 except comprising a secondary signal source 32, a comparer 12, a driver element 13, a detector 14 and a LASER Light Source (Laser head) 15.Comparer 12 comprises an operational amplifier 121, resistance R 1, R2 and capacitor C.The control mode of this automatic power controller 30 is when carrying out the different output power switching, utilize first signal source 31 to produce required control voltage signal, and utilize control module 33 to come change-over switch SW1, make power switching initial stage control voltage signal can be connected directly to driver element 13.Therefore, driver element 13 can produce desired power soon and give LASER Light Source 15.Secondly, this automatic power controller 30 utilizes switch SW 2 switching the different output power initial stage, and high voltage (Vcc) or ground voltage are directly exported to operational amplifier 121, makes the capacitor C can fast charging and discharging.At last, this automatic power controller 30 utilizes the output voltage of control module 33 detecting operational amplifiers 121 and the output voltage of first signal source 31, when both voltage near the time, the state of change-over switch SW1, SW2 makes this automatic power controller 30 recover the loop of normal operations.Though,, must additionally use a control module 33 though this automatic power controller 30 can produce required power apace, and makes operational amplifier 121 reach stable state apace.And two switch SW 1, SW2 detect the output voltage of present operational amplifier 121, and the action of gauge tap SW1, SW2, and design is comparatively complicated.
Summary of the invention
Because the problems referred to above the objective of the invention is to propose a kind of framework that uses the different gains value when different output power, make automatic power controller reach the automatic power controller of stable state fast.
For reaching above-mentioned purpose, the invention provides a kind of automatic power controller, can control the output power of the optical head of a laser disc drive unit automatically, it comprises:
One detector is the output power of detecting optical head, and produces a detection signal;
One signal source provides a reference signal, and this reference signal has different magnitudes of voltage when different output power;
One comparer is more described detection signal and described reference signal, and exports a comparison signal;
Wherein also comprise:
One switchable gain amplifier is to receive described comparison signal, and when the different voltage of described reference signal, with this comparison signal of different gain process, and produces output signal; And
One driver element is that generation one drive signal drives described optical head after receiving described output signal;
Wherein, under the different output power state, the voltage of described comparison signal all keeps equating with the voltage difference of the voltage of described reference signal.
Described comparer comprises:
One operational amplifier has the first input end and second input end, and described signal source is disposed at second input end of described operational amplifier;
One first resistance is the first input end that is disposed at described detector and described operational amplifier; And
One electric capacity is first input end and the output terminal that is disposed at described operational amplifier.
Described comparer comprises:
One gm-c integrator; And
One electric capacity is the output terminal that is disposed at described gm-c integrator.
Described automatic power controller also comprises a front-end amplifier, is to be disposed between described detector and the comparer, is used for adjusting described detection signal.
Described first signal source is a digital analog converter.
Because this automatic power controller is under the different capacity state, its comparison signal is identical with the voltage difference of reference signal, so need not wait for discharging and recharging the time of electric capacity that comparer is interior.Can shorten the time that reaches stable.
Description of drawings
Fig. 1 shows the Organization Chart of automatic power controller of the optical head of first kind of known laser disc drive unit;
When the output signal of the signal source of Fig. 2 A to 2D displayed map 1 is changed to V1b by V1a, the wave form varies of the output signal V2 of the output signal V3 of detector, operational amplifier and the voltage Vc of capacitor C;
Fig. 3 shows the Organization Chart of automatic power controller of the optical head of second kind of known laser disc drive unit;
Fig. 4 shows the Organization Chart of automatic power controller first embodiment of the optical head of laser disc drive unit of the present invention;
Fig. 5 shows the Organization Chart of automatic power controller second embodiment of the optical head of laser disc drive unit of the present invention;
Fig. 6 shows the Organization Chart of automatic power controller the 3rd embodiment of the optical head of laser disc drive unit of the present invention;
Fig. 7 shows an embodiment of the amplifier of switchable gain.
Embodiment
Describe the automatic power controller of the optical head of laser disc drive unit of the present invention in detail below with reference to Figure of description.
Fig. 4 shows the Organization Chart of automatic power controller first embodiment of the present invention.As shown in the drawing.Automatic power controller 40 is except comprising a signal source 11, a comparer 12, a driver element 13, a detector (sensor) 14 and an optical head (or LASER Light Source, Laser diode) outside 15, also comprise the amplifier (G1) 41 that is disposed at the switchable gain between comparer 12 and the driver element 13 and be disposed at detector 14 and comparer 12 between front-end amplifier (G2) 42.Comparer 12 comprises an operational amplifier 121, resistance R 1, R2 and capacitor C, and comparer 12 also can be the identical framework of other functions certainly, and resistance R 2 can be omitted.
It is to use different yield values under different capacity that automatic power controller 40 of the present invention uses the purpose of the amplifier 41 of switchable gain, when power is switched the output voltage of the voltage of the reference signal of signal source 11 and operational amplifier 121 to voltage difference equate that also soon the capacitor C of comparer 12 remains on identical voltage position.So, because the action that the capacitor C of comparer 12 need not discharge and recharge when power changes can be shortened this automatic power controller 40 and reach the needed time of stable state.Secondly, this automatic power controller 40 can be avoided operational amplifier 121 (saturated) state that reaches capacity.
When the power of the optical head of laser disc drive unit when first output power when reading state (for example power) Pa is changed to second output power when burning state (for example power) Pb, automatic power controller 40 is changed to V1b with the voltage of the reference signal of signal source 11 from V1a.At this moment, the voltage after the output voltage of comparer 12 can amplify via front-end amplifier 42 from the output voltage that V2a is changed to V2b, detector 14 is changed to V3b from V3a.Simultaneously, the yield value of switchable gain amplifier 41 is changed to G1b from G1a, and output voltage is changed to V4b from V4a.Why automatic power controller 10 shown in Figure 1 needs the long time just can reach stable state is the stable state output voltage poor (V1b-V1a) that is not equal to the reference signal of signal source 11 because of comparer 12 when power switches in the stable state output voltage of front and back power poor (V2b-V2a).The present invention is in order to address this problem, utilize switchable gain amplifier 41 when different capacity, find out suitable yield value, so that comparer 12 output voltage V 2 equal the stable state output voltage V 1 of signal source 11, or comparer 12 output voltage V 2 equate with the voltage difference of the stable state output voltage V 1 of signal source 11.Because the stable state output voltage V 2 of the comparer 12 during with different capacity is designed to equal the stable state output voltage V 1 of signal source 11, therefore the operational amplifier 121 of comparer 12 can be predicted and the state that can not reach capacity in advance, can avoid in the traditional approach operational amplifier output voltage to change with laser characteristics and cause saturated problem.In addition, because of capacitor C does not also need to carry out the extra action that discharges and recharges because of the output power switching, so its power switch speed also can significantly promote.
The account form of the yield value of amplifier 41 when different capacity of switchable gain is:
G1a＝V4a/V1a
G1b＝V4b/V1b
Fig. 5 shows the Organization Chart of automatic power controller second embodiment of the present invention.As shown in the drawing, automatic power controller 50 except comprising one first signal source 52, a comparer 12, a driver element 13, a detector 14 and an optical head 15, also comprise totalizer 51, a secondary signal source 53 that is disposed between comparer 12 and the driver element 13 and be disposed at detector 14 and comparer 12 between front-end amplifier (G2) 42.Comparer 12 comprises an operational amplifier 121, resistance R 1, R2 and capacitor C, and resistance R 2 can be omitted certainly.The otherness of the present embodiment automatic power controller 50 and the first embodiment automatic power controller 40 is to utilize secondary signal source 53 and totalizer 51 to replace the amplifier 41 of switchable gain, and its purpose is all identical with first embodiment with function.Automatic power controller 50 of the present invention is when different output powers, utilize the different offset voltages of secondary signal source 53 outputs, and the voltage and the offset voltage addition that utilize totalizer 51 that comparer 12 is exported, change the voltage that exports driver element 13 to, make the capacitor C of operational amplifier 121 can keep identical pressure drop, that is the voltage difference of the output voltage of first signal source 52 and the output voltage of 0P operational amplifier 121 all equate when different capacity.
Fig. 6 shows the Organization Chart of automatic power controller the 3rd embodiment of the present invention.As shown in the drawing, automatic power controller 60 comprises amplifier (G1) 41 and the front-end amplifier (G2) 42 of a signal source 11, a comparer 61, a driver element 13, a detector 14, an optical head 15, switchable gain.The difference of this embodiment and first embodiment is that comparer 12 is to comprise a gm-c integrator (integrator) and a capacitor C.It is to reduce an output and input pins (I/O pin) that this comparer 61 uses the purpose of a gm-c integrator 611 and a capacitor C.The action of this embodiment and first embodiment are similar, no longer repeat specification.Gm-c integrator and operational amplifier are all comparer, are high resistant Hangzhoupro but its output signal is electric current and output terminal, and therefore, the electric capacity as if directly connecting at its output terminal over the ground promptly forms electric current and enters the mechanism of electric capacity and constitute an integrator.
In addition, the automatic power controller 50 of second embodiment of Fig. 5 also can change to comparer 12 framework of the comparer 61 of Fig. 6, to reduce an output and input pins (I/O pin).
Fig. 7 shows an embodiment of the amplifier of switchable gain.As shown in the drawing, the amplifier of this switchable gain comprises an operational amplifier 71, a resistance R 1 and a variable resistor R2, and wherein variable resistor R2 connects the negative input end and the output terminal of this operational amplifier 71.If input signal Vin is connected to the negative input end of operational amplifier 71 via resistance R 1, and the positive input terminal ground connection of operational amplifier 71, then the output end voltage of this operational amplifier 71 is: Vout-Vin* (R2/R1).
Therefore, be changeable this Amplifier Gain as long as change the resistance value of variable resistor R2.For example, in first embodiment,, can reach the purpose of switching different gains as long as when different capacity, change the resistance value of variable resistor R2.
Automatic power controller of the present invention utilizes the voltage difference of output voltage that the amplifier of switchable gain makes comparer and the reference signal of signal source all to keep identical when different output power, therefore when output power changes, the electric capacity of comparer need not discharge and recharge, and uses and shortens the time that this automatic power controller reaches stable state.In addition, because automatic power controller of the present invention when output power changes, almost reaches stable state, simultaneously so do not need extra control module to detect the output voltage of comparer, and do not need extra switch to switch the signal that inputs to driver element, so framework is simpler.
Though more than with embodiment the present invention is described, therefore do not limit model figure of the present invention, only otherwise break away from main idea of the present invention, the sector person can carry out various distortion or change.
Claims (5)
1, a kind of automatic power controller, it comprises:
One detector is the output power of detecting optical head, and produces a detection signal;
One signal source provides a reference signal, and this reference signal has different magnitudes of voltage when different output power;
One comparer is more described detection signal and described reference signal, and exports a comparison signal;
It is characterized in that also comprising:
One switchable gain amplifier is to receive aforementioned comparison signal, and when the different voltage of described reference signal, with this comparison signal of different gain process, and produces output signal; And
One driver element is that generation one drive signal drives described optical head after receiving described output signal;
Wherein, under the different output power state, the voltage of described comparison signal all keeps equating with the voltage difference of the voltage of described reference signal.
2, automatic power controller as claimed in claim 1 is characterized in that: also comprising a front-end amplifier, is to be disposed between described detector and the comparer, is used for amplifying described detection signal.
3, automatic power controller as claimed in claim 1 is characterized in that: described signal source is a digital analog converter.
4, automatic power controller as claimed in claim 1 is characterized in that described comparer comprises:
One operational amplifier has the first input end and second input end, and described signal source is disposed at second input end of described operational amplifier;
One first resistance is the first input end that is disposed at described detector and described operational amplifier; And
One electric capacity is first input end and the output terminal that is disposed at described operational amplifier.
5, automatic power controller as claimed in claim 1 is characterized in that described comparer comprises: a gm-c integrator; And
One electric capacity is the output terminal that is disposed at described gm-c integrator.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100885617A CN100428103C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
| CN 03109395 CN1282960C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03109395 CN1282960C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100885617A Division CN100428103C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1536564A CN1536564A (en) | 2004-10-13 |
| CN1282960C true CN1282960C (en) | 2006-11-01 |
Family
ID=34319314
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03109395 Expired - Fee Related CN1282960C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
| CNB2006100885617A Expired - Fee Related CN100428103C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100885617A Expired - Fee Related CN100428103C (en) | 2003-04-08 | 2003-04-08 | Automatic power controller |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN1282960C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100465850C (en) * | 2005-06-21 | 2009-03-04 | 深圳市大族激光科技股份有限公司 | Laser power feedback circuit |
| US7642770B2 (en) * | 2007-03-16 | 2010-01-05 | Mediatek Inc. | Light-driving system capable of providing signal-measured calibration and a method for performing the same |
| CN109587419B (en) * | 2018-11-06 | 2021-04-30 | 上海集成电路研发中心有限公司 | Low-power-consumption reading circuit structure of image sensor and working time sequence control method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03276782A (en) * | 1990-03-27 | 1991-12-06 | Matsushita Electric Ind Co Ltd | Pulse light source |
| US5923427A (en) * | 1997-07-10 | 1999-07-13 | Banner Engineering Corporation | Optical triangulation distance sensing system and method using a position sensitive detector and an automatic power controlled light source |
| US6395690B1 (en) * | 2001-02-28 | 2002-05-28 | Unilever Home & Personal Care Usa Division Of Conopco, Inc. | Process for making mild moisturizing liquids containing large oil droplet |
-
2003
- 2003-04-08 CN CN 03109395 patent/CN1282960C/en not_active Expired - Fee Related
- 2003-04-08 CN CNB2006100885617A patent/CN100428103C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN100428103C (en) | 2008-10-22 |
| CN1866150A (en) | 2006-11-22 |
| CN1536564A (en) | 2004-10-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8253613B2 (en) | Second-order delta-sigma analog-to-digital converter | |
| US20030155967A1 (en) | Switched-capacitor amplifier and analog interface circuit for charge coupled element adopting the same | |
| CN1619931A (en) | Charge pump circuit and amplifier | |
| CN115832866B (en) | Laser drive control circuit, chip and control method | |
| US20090027116A1 (en) | Method and integrated circuit including an amplifier calibration circuit | |
| CN1282960C (en) | Automatic power controller | |
| KR930020859A (en) | Analog digital converter | |
| CN1781025A (en) | I/F conversion device and photo-detection device | |
| JP2001319424A (en) | Signal processing circuit and semiconductor integrated circuit | |
| CN1163874C (en) | Circuit and method for detecting image signal in CD driver | |
| JP3506561B2 (en) | Output circuit | |
| CN1217536C (en) | Shock sound prevention circuit | |
| US7180374B2 (en) | Photodiode integrated circuit having multiple gain states | |
| CN1619948A (en) | Amplifier | |
| CN1438771A (en) | Optical receiver ampeifier and optical pick-up device adopting said circuit | |
| US20050116769A1 (en) | Sensor device and a signal amplification device of a small detection signal provided by the sensor | |
| KR100434236B1 (en) | A motor control driving circuit | |
| TWI225190B (en) | Automatic power controller | |
| CN111257625A (en) | Integral comparator for detecting weak voltage signal in power control of semiconductor laser | |
| US5003378A (en) | Automatic white balance circuit | |
| US6246285B1 (en) | AGC circuit based on a peak detection system | |
| US6236898B1 (en) | Error compensation circuit for compensating for parameter errors of an IC chip having a filter and a boost circuit | |
| JP2002158396A (en) | Auto laser power control circuit | |
| JPH09266353A (en) | Digital light power control circuit | |
| WO2021154881A1 (en) | Mitigating reliability issues in a low-voltage reference buffer driven by a high-voltage circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20061101 Termination date: 20160408 |