CN105242739A - Temperature control bias current supply circuit, bias current temperature control method and laser driver - Google Patents
Temperature control bias current supply circuit, bias current temperature control method and laser driver Download PDFInfo
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- CN105242739A CN105242739A CN201510726438.2A CN201510726438A CN105242739A CN 105242739 A CN105242739 A CN 105242739A CN 201510726438 A CN201510726438 A CN 201510726438A CN 105242739 A CN105242739 A CN 105242739A
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Abstract
The invention provides a temperature control bias current supply circuit, a bias current temperature control method and a laser driver employing the temperature control bias current supply circuit. By using the temperature-resistance change relationship of an NTC thermistor, the temperature control change of voltage is realized and further the temperature control change of bias current is realized. The problems that a laser bias current supply circuit in the prior art requires many components, much PCB layout space is occupied and some component ports are not fully utilized are solved. According to the invention, the topological circuit for laser bias current temperature control is simplified, the component cost of the laser driver is reduced and the utilization rate of the components is increased.
Description
Technical field
The present invention relates to optical communication field, particularly relate to a kind of temperature control bias current supply circuit, bias current Temp. control method and laser driver.
Background technology
In optical communication system, the performance characteristics of laser instrument is that parameter can change along with temperature, and along with the rising of temperature, very large drift can occur the threshold current of laser diode, and electro-optical efficiency can successively decrease thereupon simultaneously.Laser driver is the important component of transmitting terminal as laser instrument, for laser instrument provides required drive current, drive current comprises modulating current and bias current, and modulating current is exactly the high-speed digital signal of transmission, and bias current is mainly used in the threshold value of opening laser instrument.
In the temperature range being operated in-40 DEG C to+85 DEG C that laser instrument requires, average light power is stablized, but because during temperature variation, the threshold current of laser instrument can change, and in order to ensure that average light power is constant, just needs the size adjusting bias current according to the temperature variation characteristic of laser diode.
The size adopting automated power control mode to adjust bias current in prior art more, as shown in Figure 1, triode is varied with temperature and the change in voltage produced, generation difference is compared with reference voltage Vref, difference is amplified through operational amplifier chip, remove the base voltage Vb controlling amplifying circuit triode, thus amplification flows through from collector the bias current Ibias penetrating level, to realize the change that bias current Ibias varies with temperature to adapt to laser temperature characteristic.
The above-mentioned core of bias current temperature control circuit and the main points of realization are to enable base voltage Vb rise with temperature and increase, and decline and reduce with temperature.But the Vb change control method adopted in above-mentioned temperature control circuit need use triode and operational amplifier chip, the PCB arrangement space taken is many, and operational amplifier several roads amplification simultaneously does not all utilize, and also has 1 tunnel vacant.
Therefore, consider fabric swatch space resources, realize cost, chip utilization factor, above-mentioned bias current temperature control circuit implementation efficiency non-optimal, there is the space that can optimize.
Summary of the invention
In view of this, in order to the components and parts needed for existing laser bias current temperature control circuit are more, the PCB arrangement space taken is many, and the problem that part components and parts port is not fully utilized, the invention provides a kind of temperature control bias current supply circuit, by utilizing simple thermistor to replace original complicated circuit, reducing taking of PCB arrangement space, providing the utilization factor of components and parts.
In order to solve the problem, temperature control bias current supply circuit of the present invention, is applied to laser driver, comprises:
Temperature adjustable voltage division circuit, its voltage input end connects direct supply VCC, and carry out dividing potential drop to direct supply VCC, the controllable voltage Vb needed for bias current generating circuit, the value of controllable voltage Vb increases with the rising of laser temperature;
Bias current generating circuit, connects the voltage output end of described temperature adjustable voltage division circuit, for described laser instrument provides temperature variant bias current I
bias.
Wherein, temperature adjustable voltage division circuit comprises: the parallel branch that negative tempperature coefficient thermistor RT and resistance R1 is formed and resistance R2, one end of parallel branch connects power supply VCC, the other end is by resistance R2 ground connection, one end that parallel branch is connected with resistance R2 is set to voltage output end, and the dividing potential drop on resistance R2 is as described controllable voltage Vb.
Correspondingly, present invention also offers a kind of bias current Temp. control method, comprise the following steps:
Obtain ideal value Vb' and the error burst of the controllable voltage Vb of laser instrument in the temperature range of normal work needed for bias current generating circuit;
Utilize negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 to set up temperature adjustable voltage division circuit and provide described controllable voltage Vb for described bias current generating circuit, set up the expression formula of described controllable voltage Vb;
Make described controllable voltage Vb and the error described in it between ideal value Vb' within the scope of described error burst, obtain the resistance of negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 described in described temperature adjustable voltage division circuit;
Described temperature adjustable voltage division circuit provides temperature variant described controllable voltage Vb for described laser instrument in the temperature range of described normal work.
Wherein, the acquisition of described ideal value Vb' and error burst comprises the following steps:
The temperature range of described normal work is divided between low-temperature range and high-temperature region, at described low-temperature range with 20 DEG C for sample temperature point is chosen at interval, between described high-temperature region with 5 DEG C for sample temperature point is chosen at interval, described low-temperature range is [-40 DEG C, 20 DEG C], between described high-temperature region be (20 DEG C, 85 DEG C];
To a sample temperature point, observe the light eye pattern that described laser instrument exports light, base voltage Vb time best using light eye pattern needed for bias current generating circuit is as the ideal value Vb' of this sample temperature point; The described base voltage Vb of further adjustment, observes the change of described smooth eye pattern, record described smooth eye pattern be deteriorated the base voltage Vb to correspondence, draw the error burst of this sample temperature point;
Get the common factor of the error burst of all sample temperatures point, as the error burst solving each resistance in described temperature adjustable voltage division circuit.
Further, the resistance obtaining negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 described in described temperature adjustable voltage division circuit adopts EXCEL Programming.
The present invention also provides a kind of laser driver comprising above-mentioned temperature control bias current supply circuit.
Compared with prior art, the present invention has following advantage: temperature control bias current supply circuit of the present invention, bias current Temp. control method and adopt the laser driver of this temperature control bias current supply circuit to make use of the variation relation of the temperature-resistance of NTC thermistor, achieve the temperature control change of voltage, realize the temperature control change of bias current with this further.The temperature achieving laser works bias current with very little circuit topological structure and considerably less Material Cost controls, and improves the utilization factor of components and parts.
Accompanying drawing explanation
Fig. 1 is that existing bias current produces and temperature control circuit;
Fig. 2 is the connection diagram of laser driver and laser instrument in the present invention;
Fig. 3 is temperature control bias current supply circuit schematic diagram in the present invention;
Fig. 4 is temperature adjustable voltage division circuit structural drawing;
Fig. 5 is bias current generating circuit structural drawing;
Fig. 6 is the ideal value Vb' of temperature adjustable voltage division circuit output voltage and the comparison diagram of actual value Vb.
Embodiment
Below in conjunction with embodiment, the present invention is further described.
Laser driver in Fig. 2 comprises temperature control bias current supply circuit 1, laser drive circuit 2, and laser drive circuit 2 provides modulating current I for laser instrument 3
mod, temperature control bias current supply circuit 1 for laser instrument 3 provides can temperature variant bias current I
bias.
In Fig. 3, temperature control bias current supply circuit comprises: temperature adjustable voltage division circuit 11 and bias current generating circuit 12, temperature adjustable voltage division circuit 11 connects power supply VCC, carry out dividing potential drop with the performance change of temperature to supply voltage according to laser instrument 3 and provide temperature variant controllable voltage Vb for bias current generating circuit 12, temperature control bias current supply circuit 1 produces under the effect of voltage Vb can temperature variant bias current I
bias.
In Fig. 4, temperature adjustable voltage division circuit 11 comprises parallel branch and the resistance R2 of negative tempperature coefficient thermistor (NTC thermistor) RT and resistance R1, one end of parallel branch connects power supply VCC, the other end is by resistance R2 ground connection, one end that parallel branch is connected with resistance R2 is provided with voltage output end, and the dividing potential drop on resistance R2 is as the controllable voltage Vb of bias current generating circuit 12.Above-mentioned resistance R1 and resistance R2 adopts 1% precision resistance best.
From temperature adjustable voltage division circuit 11 in Fig. 4, RT, R1 parallel equivalent resistance=RT × R1/ (RT+R1), then the value of output voltage Vb is: Vb=VCC × R2/ [R2+RT × R1/ (RT+R1)], resistance RT=R25 × the exp{BN [1/ (T+273)-1/298] of NTC thermistor }, in formula, R25 represents the specified zero-power resistance of this thermistor when normal temperature 25 degree, T is temperature (thermodynamic temperature, unit is K), BN is the material constant of NTC thermistor, be heat sensitive index again, index (the e=2.71828 that it is the end that exp represents with natural number e ...).
The base stage of the triode Q in Fig. 5 in bias current generating circuit 12 connects the voltage output end of temperature adjustable voltage division circuit 11, and by electric capacity C ground connection; Launch collection by resistance R3 ground connection, collector is by resistance R4 connecting laser 3, the base voltage Vb of triode Q changes, the electric current I CE flowing through emitter from collector then changes accordingly, for the bias current Ibias that laser instrument provides, △ Ibias=△ Vb/R3, △ represents variable quantity.
In said temperature adjustable voltage division circuit 11, the resistance of negative tempperature coefficient thermistor RT, resistance R1, resistance R2 is determined by following steps:
(1) laser instrument voltage Vb ideal value Vb' required within the scope of normal working temperature and error burst is obtained
The normal working temperature interval of laser instrument is :-40 DEG C ~ 85 DEG C, in the performance design process of laser instrument, pay the utmost attention to the performance of condition of high temperature laser instrument, therefore the temperature range normally worked is divided into low-temperature range [-40 DEG C, 20 DEG C] and high-temperature region between (20 DEG C, 85 DEG C], low temperature section interval with 20 DEG C for sample temperature point is chosen at interval, between high-temperature petiolarea with 5 DEG C for sample temperature point is chosen at interval, obtain series of temperature point-40,-20, 0, 20, 25, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, the magnitude of voltage of power supply VCC is set to 3.3V.
Simulate by experiment, the experimental voltage value of the base voltage needed for bias current generating circuit is debugged respectively under each sample temperature point, make the eye pattern of the output light of connecting laser in oscillograph best, then the ideal value Vb' under each temperature spot is depicted as a optimal compensation curve; Further regulation experiment magnitude of voltage, observes the change of described smooth eye pattern, and the experimental voltage corresponding to recording light eye pattern is deteriorated, draws the error burst of this sample temperature point; Get the common factor of the error burst of all sample temperatures point, as final error burst, show that error between voltage Vb and ideal value Vb' is within the scope of ± 0.5V, eye pattern state all can think optimum condition.
(2) resistance solving resistance R1 and resistance R2 makes the curve of voltage Vb approach the curve of ideal value Vb'.
According to the temperature adjustable voltage division circuit 11 in Fig. 4, resistor network topology is set, connect each components and parts and the laser instrument of laser drive circuit, make the change direction of the output voltage Vb of temperature control bias current supply circuit 1 consistent with the magnitude of voltage Vb' change direction of actual needs.Like this, just obtain compensate with original more complicated implementation laser instrument closely relatively to save PCB cloth board space and to save the mode of Material Cost.
Presetting R1, R2 resistance initial value to be solved, then utilize software to carry out iterative computation, in the hope of meeting | the optimum solution of Vb-Vb'|≤0.5, the performance of optimum solution is relevant with the size of initial value and iterations.Such as the present embodiment calculates the value of each element in resistor network by the functional simulation of EXCEL programming evaluation, makes Vb change curve and tests that to survey the desired voltage Vb' curve that device needs consistent as far as possible.
EXCEL programming evaluation function is also referred to as what-if instrument, that is: what-if process checks these impact of change on formulae results in worksheet by the value in changing unit lattice.By programming evaluation, as shown in table 1, process to direct or indirect one group of cell relevant to the formula in Set cell, the optimal value of formula in certain Set cell on worksheet can be tried to achieve.The value of variation cell R1, R2 specified by adjustment, tries to achieve specified result from Set cell formula.
The form of table 1EXCEL programming evaluation resistance R1 and resistance R2
Solution procedure is as follows:
As shown in Figure 6, the target voltage Vb=0.52V that laser instrument is required at normal temperatures, according to formula:
Vb=3.3V × R2/ [R2+RT × R1/ (RT+R1)] show that the ratio relation of the equivalent resistance of R1//RT and R2 resistance at normal temperatures should close to 6:1;
Consider that the power consumption of resistance pressure-dividing network should be little as far as possible, therefore resistance R1, R2 all should adopt the resistance of 10K rank, according to result of calculation, in conjunction with the gear of 1% precision resistance, the initial value of setting R1 and R2 is: R2=10K Ω, R1=62K Ω, the thermistor RT in parallel with R1 should much larger than 62K Ω simultaneously, and the equivalent resistance after such resistance R1 is in parallel with thermistor RT just can more close to 62K Ω.
The series specification of thermistor commonly used by table 2
The series specification of conventional thermistor optional in table 2 is brought in the computing formula of above-mentioned Vb, draws and select normal temperature resistance 470K Ω, the Vb curve overall trend relatively aim curve obtained.Determine the gear according to 1% precision resistance after thermistor specification, by R1, R2 finely tunes and substitutes into calculating, finally determine R2=10K Ω or 12K Ω, R1=62K Ω, can find out that the ideal value Vb' of temperature adjustable voltage division circuit output voltage in Fig. 6 is consistent with the change curve of actual value Vb, and the actual value Vb on each temperature spot is all near ideal value Vb'.
More than describe the preferred embodiment of the present invention in detail; but the present invention is not limited to the detail in above-mentioned embodiment, within the scope of technical conceive of the present invention; can carry out multiple equivalents to technical scheme of the present invention, these equivalents all belong to protection scope of the present invention.
Claims (7)
1. a temperature control bias current supply circuit, is applied to laser driver, it is characterized in that, comprising:
Temperature adjustable voltage division circuit, its voltage input end connects direct supply VCC, and carry out dividing potential drop to direct supply VCC, the controllable voltage Vb needed for bias current generating circuit, the value of controllable voltage Vb increases with the rising of laser temperature;
Bias current generating circuit, connects the voltage output end of described temperature adjustable voltage division circuit, for described laser instrument provides temperature variant bias current I
bias.
2. temperature control bias current supply circuit according to claim 1, it is characterized in that, described temperature adjustable voltage division circuit comprises: the parallel branch that negative tempperature coefficient thermistor RT and resistance R1 is formed and resistance R2, one end of parallel branch connects power supply VCC, the other end is by resistance R2 ground connection, one end that parallel branch is connected with resistance R2 is set to described voltage output end, and the dividing potential drop on resistance R2 is as described controllable voltage Vb.
3. temperature control bias current supply circuit according to claim 1, it is characterized in that, described bias current generating circuit comprises: triode Q, and the base stage of described triode Q connects described voltage output end, and by electric capacity C ground connection; Launch collection by resistance R3 ground connection, collector connects described laser instrument by resistance R4, and the electric current flowing through emitter from collector is described bias current I
bias.
4. a bias current Temp. control method, is applied to laser driver, it is characterized in that, comprises the following steps:
Obtain ideal value and the error burst of the controllable voltage Vb of laser instrument in the temperature range of normal work needed for bias current generating circuit;
Utilize negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 to set up temperature adjustable voltage division circuit and provide described controllable voltage Vb for described bias current generating circuit, set up the expression formula of described controllable voltage Vb;
Make described controllable voltage Vb and the error described in it between ideal value within the scope of described error burst, obtain the resistance of negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 described in described temperature adjustable voltage division circuit;
Described temperature adjustable voltage division circuit provides temperature variant described controllable voltage Vb for described laser instrument in the temperature range of described normal work.
5. bias current Temp. control method according to claim 4, is characterized in that, the acquisition of described ideal value and error burst comprises the following steps:
The temperature range of described normal work is divided between low-temperature range and high-temperature region, at described low-temperature range with 20 DEG C for sample temperature point is chosen at interval, between described high-temperature region with 5 DEG C for sample temperature point is chosen at interval, described low-temperature range is [-40 DEG C, 20 DEG C], between described high-temperature region be (20 DEG C, 85 DEG C];
To a sample temperature point, observe the light eye pattern that described laser instrument exports light, base voltage Vb time best using light eye pattern needed for bias current generating circuit is as the ideal value of this sample temperature point; The described base voltage Vb of further adjustment, observes the change of described smooth eye pattern, record described smooth eye pattern be deteriorated the base voltage Vb to correspondence, draw the error burst of this sample temperature point;
Get the common factor of the error burst of all sample temperatures point, as the error burst solving each resistance in described temperature adjustable voltage division circuit.
6. bias current Temp. control method according to claim 5, is characterized in that, the resistance obtaining negative tempperature coefficient thermistor RT, resistance R1 and resistance R2 described in described temperature adjustable voltage division circuit adopts EXCEL programming evaluation.
7. a laser driver, is characterized in that, comprises the temperature control bias current supply circuit in claims 1 to 3 described in any one.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106155688A (en) * | 2016-07-05 | 2016-11-23 | 江苏奥雷光电有限公司 | A kind of linear deflection algorithm with lower limit being applicable to optical module production |
| CN112909735A (en) * | 2021-01-19 | 2021-06-04 | 索尔思光电（成都）有限公司 | Multi-channel laser bias current correction circuit and method |
| CN114756070A (en) * | 2022-04-01 | 2022-07-15 | 苏州海光芯创光电科技股份有限公司 | Design method of silicon optical chip capable of automatically controlling temperature |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6055252A (en) * | 1998-09-10 | 2000-04-25 | Photonic Solutions, Inc. | Fiberoptic transmitter using thermistor to maintain stable operating conditions over a range of temperature |
| US6242870B1 (en) * | 1997-10-16 | 2001-06-05 | Fujitsu Limited | Light emitting device driving circuit |
| CN1543028A (en) * | 2003-03-13 | 2004-11-03 | 阿尔卑斯电气株式会社 | Driving circuit for semiconductor laser |
| CN1883090A (en) * | 2003-11-18 | 2006-12-20 | 松下电器产业株式会社 | Laser driving device, optical head comprising laser driving device, and optical disk device |
| CN101453270A (en) * | 2007-12-04 | 2009-06-10 | 无锡江南计算技术研究所 | Laser driver and temperature compensation circuit thereof |
| CN201413927Y (en) * | 2009-06-17 | 2010-02-24 | 深圳新飞通光电子技术有限公司 | APC AND cut-off circuit for electroabsorption externally-modulated laser |
| CN203014159U (en) * | 2012-11-01 | 2013-06-19 | 西安华科光电有限公司 | Laser |
-
2015
- 2015-10-30 CN CN201510726438.2A patent/CN105242739B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6242870B1 (en) * | 1997-10-16 | 2001-06-05 | Fujitsu Limited | Light emitting device driving circuit |
| US6055252A (en) * | 1998-09-10 | 2000-04-25 | Photonic Solutions, Inc. | Fiberoptic transmitter using thermistor to maintain stable operating conditions over a range of temperature |
| CN1543028A (en) * | 2003-03-13 | 2004-11-03 | 阿尔卑斯电气株式会社 | Driving circuit for semiconductor laser |
| CN1883090A (en) * | 2003-11-18 | 2006-12-20 | 松下电器产业株式会社 | Laser driving device, optical head comprising laser driving device, and optical disk device |
| CN101453270A (en) * | 2007-12-04 | 2009-06-10 | 无锡江南计算技术研究所 | Laser driver and temperature compensation circuit thereof |
| CN201413927Y (en) * | 2009-06-17 | 2010-02-24 | 深圳新飞通光电子技术有限公司 | APC AND cut-off circuit for electroabsorption externally-modulated laser |
| CN203014159U (en) * | 2012-11-01 | 2013-06-19 | 西安华科光电有限公司 | Laser |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106155688A (en) * | 2016-07-05 | 2016-11-23 | 江苏奥雷光电有限公司 | A kind of linear deflection algorithm with lower limit being applicable to optical module production |
| CN112909735A (en) * | 2021-01-19 | 2021-06-04 | 索尔思光电（成都）有限公司 | Multi-channel laser bias current correction circuit and method |
| CN112909735B (en) * | 2021-01-19 | 2022-09-16 | 索尔思光电（成都）有限公司 | Multi-channel laser bias current correction circuit and method |
| CN114756070A (en) * | 2022-04-01 | 2022-07-15 | 苏州海光芯创光电科技股份有限公司 | Design method of silicon optical chip capable of automatically controlling temperature |
| CN114756070B (en) * | 2022-04-01 | 2024-06-11 | 苏州海光芯创光电科技股份有限公司 | Design method of silicon optical chip with automatic temperature control function |
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