Projector system, driving device and driving method of light-emitting device thereof
阅读说明:本技术 投影机系统、驱动装置及其发光装置的驱动方法 (Projector system, driving device and driving method of light-emitting device thereof ) 是由 许善程 许嘉文 许胜鑫 于 2018-07-27 设计创作,主要内容包括:一种投影机系统、驱动装置及其发光装置的驱动方法。驱动装置包括控制信号产生器、电压准位隔离器以及电源转换器。控制信号产生器提供第一控制信号对。电压准位隔离器具有输入端电路以及输出端电路。输入端电路接收第一控制信号对,输出端电路依据第一控制信号对以产生第二控制信号对。输出端电路的电压耐受度高于输入端电路的电压耐受度。电源转换器依据第二控制信号对以转换第一电源来产生第二电源,并提供第二电源以驱动发光装置。本发明可有效驱动较高驱动电压的发光装置。(A projector system, a driving device and a driving method of a light emitting device thereof are provided. The driving device comprises a control signal generator, a voltage level isolator and a power converter. The control signal generator provides a first control signal pair. The voltage level isolator has an input terminal circuit and an output terminal circuit. The input end circuit receives a first control signal pair, and the output end circuit generates a second control signal pair according to the first control signal pair. The voltage tolerance of the output-side circuit is higher than that of the input-side circuit. The power converter converts the first power to generate a second power according to the second control signal pair, and provides the second power to drive the light-emitting device. The invention can effectively drive the light-emitting device with higher driving voltage.)
1. A driving device for driving a light emitting device, the driving device comprising:
a control signal generator providing a first control signal pair;
the voltage quasi-position isolator is provided with an input end circuit and an output end circuit, wherein the input end circuit receives the first control signal pair, and the output end circuit generates a second control signal pair according to the first control signal pair, wherein the voltage tolerance of the output end circuit is higher than that of the input end circuit; and
the power converter converts the first power to generate a second power according to the second control signal pair and provides the second power to drive the light-emitting device.
2. The driving apparatus as claimed in claim 1, wherein the power converter comprises:
a first transistor, a first terminal of which receives the first power supply, a second terminal of which is connected to a center terminal, and a control terminal of which receives a high-side control signal of the second control signal pair;
a second transistor, a first terminal of which is coupled to the center terminal, a second terminal of which is coupled to a first reference ground terminal, and a control terminal of which receives a low-side control signal of the second control signal pair; and
an inductor, a first terminal of the inductor coupled to the center terminal, a second terminal of the inductor generating the second power.
3. The driving apparatus as claimed in claim 2, wherein the power converter performs a step-down voltage conversion for the first power to generate the second power, wherein the voltage value of the first power is greater than the voltage value of the second power.
4. The driving apparatus as claimed in claim 2, wherein the output terminal circuit comprises:
a first output driver coupled between a pull-up power source and the center terminal, for generating the high-side control signal according to a voltage of the pull-up power source, a voltage of the center terminal, and a first signal of the first control signal pair; and
the second output driver is coupled between a third power supply and a second reference ground terminal, and generates the low-side control signal according to the voltage at the center terminal and a second signal of the first control signal pair.
5. The drive of claim 4, further comprising:
the pull-up circuit is coupled to the first output driver and the center terminal, receives a boot strap voltage, and generates the pull-up power according to the boot strap voltage.
6. The driving apparatus as claimed in claim 5, wherein the pull-up circuit comprises:
a diode, an anode of the diode receiving the bootstrap voltage, and a cathode of the diode providing the pull-up power; and
and the capacitor is coupled between the cathode of the diode and the central end in series.
7. The driving apparatus as claimed in claim 4, wherein the input terminal circuit comprises:
a first buffer for receiving the first signal and providing a first buffered signal;
a second buffer receiving the second signal and providing a second buffered signal;
a level shifter for shifting the first and second buffered signals to generate a first and second voltage offset signals, respectively;
the undervoltage locking circuit is used for detecting whether the voltages of the pull-up power supply and the third power supply are too low or not so as to generate a locking signal; and
a logic operator, for performing operations on the locking signal and the first voltage offset signal and the second voltage offset signal respectively to generate a third signal and a fourth signal respectively;
the third signal and the fourth signal are respectively provided to the control ends of the first output driver and the second output driver.
8. The driving apparatus as claimed in claim 7, wherein the first output driver comprises:
a third transistor, a first end of which receives the pull-up power source, a second end of which generates the high-side control signal, and a control end of which receives the third signal; and
a fourth transistor, a first terminal of which is coupled to the second terminal of the third transistor, a second terminal of which is coupled to the center terminal, and a control terminal of which receives the third signal.
9. The driving apparatus as claimed in claim 7, wherein the second output driver comprises:
a third transistor, a first end of which receives the third power supply, a second end of which generates the low-side control signal, and a control end of which receives the fourth signal; and
a fourth transistor, wherein a first terminal of the fourth transistor is coupled to a second terminal of the fourth transistor, a second terminal of the fourth transistor is coupled to the second reference ground terminal, and a control terminal of the fourth transistor receives the fourth signal.
10. The driving apparatus as claimed in claim 7, wherein the first buffer and the second buffer are hysteresis type buffers.
11. The drive of claim 7, further comprising:
a diode, the cathode of which is coupled to the first buffer, and the anode of which is coupled to a third reference ground terminal;
a first resistor coupled in parallel with the diode;
a second resistor coupled between the second buffer and the third reference ground; and
and the capacitor is coupled in series between paths of the first buffer for receiving the first signal.
12. The drive of claim 7, further comprising:
a pull-up circuit coupled to the control signal generator for setting a voltage level of the first signal.
13. The driving apparatus as claimed in claim 12, wherein the pull-up circuit comprises:
a diode, an anode of the diode receiving a reference voltage; and
and the capacitor is coupled between the cathode of the diode and a third reference grounding end in series.
14. The drive of claim 4, further comprising:
a first resistor coupled in series between the first output driver and the control terminal of the first transistor;
a second resistor coupled in series between the control terminal and the center terminal of the first transistor;
a third resistor coupled in series between the second output driver and the control terminal of the second transistor;
a fourth resistor coupled in series between the control terminal of the second transistor and the second reference ground terminal;
a first diode, a cathode of the first diode being coupled to the control terminal of the first transistor, an anode of the first diode being coupled to the center terminal; and
and the cathode of the second diode is coupled to the control end of the second transistor, and the anode of the second diode is coupled to the second reference grounding end.
15. The driving apparatus as claimed in claim 1, wherein the light emitting means comprises at least one laser diode string or at least one light emitting diode string.
16. A projector system, comprising a lens, a light emitting device, and a driving device, wherein:
the light-emitting device comprises at least one diode string for projecting an output light beam to the lens; and
the driving device is used for driving the light-emitting device and comprises a control signal generator, a voltage level isolator and a power converter, wherein:
the control signal generator provides a first control signal pair;
the voltage level isolator is provided with an input end circuit and an output end circuit, wherein the input end circuit receives the first control signal pair, and the output end circuit generates a second control signal pair according to the first control signal pair, wherein the voltage tolerance of the output end circuit is higher than that of the input end circuit; and
the power converter converts the first power to generate a second power according to the second control signal pair, and provides the second power to drive the light-emitting device.
17. The projector system as in claim 16, wherein the power converter comprises:
a first transistor, a first terminal of which receives the first power supply, a second terminal of which is connected to a center terminal, and a control terminal of which receives a high-side control signal of the second control signal pair;
a second transistor, a first terminal of which is coupled to the center terminal, a second terminal of which is coupled to a first reference ground terminal, and a control terminal of which receives a low-side control signal of the second control signal pair; and
an inductor, a first terminal of the inductor coupled to the center terminal, a second terminal of the inductor generating the second power.
18. The projector system as recited in claim 17, wherein the power converter performs a buck conversion operation on the first power source to generate the second power source, wherein a voltage value of the first power source is greater than a voltage value of the second power source.
19. The projector system as defined in claim 17 wherein the output circuit comprises:
a first output driver coupled between a pull-up power source and the center terminal, for generating the high-side control signal according to a voltage of the pull-up power source, a voltage of the center terminal, and a first signal of the first control signal pair; and
the second output driver is coupled between a third power supply and a second reference ground terminal, and generates the low-side control signal according to the voltage at the center terminal and a second signal of the first control signal pair.
20. The projector system as defined in claim 19 wherein the drive means further comprises:
the pull-up circuit is coupled to the first output driver and the center terminal, receives a boot strap voltage, and generates the pull-up power according to the boot strap voltage.
21. The projector system as defined in claim 20, wherein the pull-up circuit comprises:
a diode, an anode of the diode receiving the bootstrap voltage, and a cathode of the diode providing the pull-up power; and
and the capacitor is coupled between the cathode of the diode and the central end in series.
22. The projector system as defined in claim 19 wherein the input circuit comprises:
a first buffer for receiving the first signal and providing a first buffered signal;
a second buffer receiving the second signal and providing a second buffered signal;
a level shifter for shifting the first and second buffered signals to generate a first and second voltage offset signals, respectively;
the undervoltage locking circuit is used for detecting whether the voltages of the pull-up power supply and the third power supply are too low or not so as to generate a locking signal; and
a logic operator, for performing operations on the locking signal and the first voltage offset signal and the second voltage offset signal respectively to generate a third signal and a fourth signal respectively;
the third signal and the fourth signal are respectively provided to the control ends of the first output driver and the second output driver.
23. The projector system as defined in claim 22, wherein the first output driver comprises:
a third transistor, a first end of which receives the pull-up power source, a second end of which generates the high-side control signal, and a control end of which receives the third signal; and
a fourth transistor, a first terminal of which is coupled to the second terminal of the third transistor, a second terminal of which is coupled to the center terminal, and a control terminal of which receives the third signal.
24. The projector system as defined in claim 22 wherein the second output driver comprises:
a third transistor, a first end of which receives the third power supply, a second end of which generates the low-side control signal, and a control end of which receives the fourth signal; and
a fourth transistor, wherein a first terminal of the fourth transistor is coupled to a second terminal of the fourth transistor, a second terminal of the fourth transistor is coupled to the second reference ground terminal, and a control terminal of the fourth transistor receives the fourth signal.
25. The projector system as in claim 22, wherein the first buffer and the second buffer are hysteresis-type buffers.
26. The projector system as defined in claim 22 wherein the drive means further comprises:
a pull-up circuit coupled to the control signal generator for setting a voltage level of the first signal.
27. The projector system as defined in claim 26, wherein the pull-up circuit comprises:
a diode, an anode of the diode receiving a reference voltage; and
and the capacitor is coupled between the cathode of the diode and a third reference grounding end in series.
28. A driving method of a light emitting device, comprising:
providing a control signal generator to generate a first control signal pair;
providing a voltage level isolator, receiving the first control signal pair by an input end circuit of the voltage level isolator, and generating a second control signal pair by an output end circuit of the voltage level isolator according to the first control signal pair, wherein the voltage tolerance of the output end circuit is higher than that of the input end circuit; and
and providing a power converter to convert the first power supply to generate a second power supply according to the second control signal pair, and providing the second power supply to drive the light-emitting device.
Technical Field
The present invention relates to a projector system, a driving apparatus and a driving method of a light emitting device thereof, and more particularly, to a driving apparatus and a driving method of a light emitting device applicable to a high driving voltage.
Background
In high-order projection systems, the demand for light sources is increasing, and thus the number of light sources is also increasing. As a result, the larger number of light sources increases the size of the projection system and increases the cost.
In the prior art, the number of laser diode strings is reduced, but the number of laser diodes in each laser diode string is increased, and the driving voltage corresponding to each laser diode string is increased, so as to meet the design requirement of the light source, wherein the driving voltage is generated by the power converter. Under such a premise, the control signal generator for providing the control signal for driving the power converter may have insufficient voltage endurance due to the relatively high voltage applied thereto, based on the phenomenon that the voltage applied to the laser diode string (load side) increases. If the voltage-withstanding capability of the control signal generator is improved, the cost of the projector system will be increased.
The background section is provided to aid in understanding the present disclosure, and it is therefore intended that the disclosure in the background section may include additional art that does not form the part of the prior art that is not already known to those of ordinary skill in the art. The statements in the "background" section do not represent that matter or the problems which may be solved by one or more embodiments of the present invention, but are known or appreciated by those skilled in the art before filing the present application.
Disclosure of Invention
The invention provides a projector system, a driving device and a driving method of a light-emitting device thereof, which can effectively drive the light-emitting device with higher driving voltage.
Other objects and advantages of the present invention will be further understood from the technical features disclosed in the present invention.
To achieve one or a part of or all of the above or other objects, a driving device according to an embodiment of the present invention is used for driving a light emitting device. The driving device comprises a control signal generator, a voltage level isolator and a power converter. The control signal generator provides a first control signal pair. The voltage level isolator has an input terminal circuit and an output terminal circuit. The input end circuit receives a first control signal pair, and the output end circuit generates a second control signal pair according to the first control signal pair. The voltage tolerance of the output-side circuit is higher than that of the input-side circuit. The power converter converts the first power to generate a second power according to the second control signal pair, and provides the second power to drive the light-emitting device.
To achieve one or a part of or all of the above or other objects, a projector system according to an embodiment of the invention includes a lens, a light-emitting device, and a driving device as described above. The light emitting device includes at least one diode string and projects an output beam to the lens.
To achieve one or a part of or all of the above or other objects, a driving method of a light emitting device according to an embodiment of the present invention includes: providing a control signal generator to generate a first control signal pair; providing a voltage level isolator, receiving a first control signal pair by an input end circuit of the voltage level isolator, and generating a second control signal pair by an output end circuit of the voltage level isolator according to the first control signal pair, wherein the voltage tolerance of an output end circuit is higher than that of the input end circuit; and providing a power converter to convert the first power supply to generate a second power supply according to the second control signal pair, and providing the second power supply to drive the light-emitting device.
Based on the above, the embodiment of the invention isolates the control signal generator at the low voltage end and the power converter at the high voltage end by the voltage level isolator, so that the control signal generator does not need to bear the high voltage in the power converter, thereby preventing the control signal generator from being burnt and maintaining the normal working state. Therefore, when the voltage value received by the power converter is increased, the driving device can still maintain normal operation.
In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.
Brief description of the drawings
Fig. 1 shows a schematic view of a driving apparatus according to an embodiment of the present invention.
Fig. 2 shows an implementation of a power converter of an embodiment of the invention.
FIG. 3 is a schematic diagram of an embodiment of a voltage level isolator according to the present invention.
Fig. 4 shows a schematic view of a drive device according to another embodiment of the invention.
FIG. 5 shows a schematic view of a projection system according to an embodiment of the invention.
Fig. 6 is a flowchart illustrating a driving method of a light emitting device according to an embodiment of the present invention.
Detailed Description
The foregoing and other features and advantages of the invention will be apparent from the following, more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings. Directional terms as referred to in the following examples, for example: up, down, left, right, front or rear, etc., are simply directions with reference to the drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.
Referring to fig. 1, fig. 1 is a schematic diagram illustrating a driving device according to an embodiment of the invention. The
The
Specifically, the input-
The
The
Referring to fig. 2, fig. 2 shows an implementation manner of a power converter according to an embodiment of the invention. The
In the present embodiment, the
It should be noted that, in order to provide the control signals DRH and DRL with appropriate voltage values to drive the transistors T1 and T2, respectively, the center terminal SW is coupled to the output terminal circuit (e.g., the
Referring to fig. 3, fig. 3 is a schematic diagram illustrating an implementation of the voltage level isolator according to an embodiment of the invention. The
In detail, a voltage comparator circuit may be disposed in the under-
The
Incidentally, when the voltage value of at least one of the pull-up power supply VDD1 and the power supply VDD2 is not high enough, the
The
In the present embodiment, the pull-up power supply VDD1 is provided by the pull-up
In this embodiment, the
In this embodiment, the voltage value of the control signal DRH may transition between the pull-up power VDD1 and the voltage at the center terminal SW, and the voltage value of the control signal DRL may transition between the power VDD2 and the voltage at the reference ground terminal GND.
Referring to fig. 3 and fig. 4, fig. 4 is a schematic diagram of a driving device according to another embodiment of the invention. The driving
The
On the other hand, the capacitor C5 is coupled in series between the cathode of the diode D3 and the center terminal SW, and the capacitor C5 and the diode D3 form a pull-up circuit.
The wire for transmitting the control signal CTH further includes a capacitor C3, a resistor R1, and a diode D4, wherein the resistor R1 is coupled in parallel with the diode D4. In the present embodiment, the capacitor C3 is coupled in series between the paths of the
On the other hand, on the conductor transmitting the control signal DRH, resistors R3, R4 and a diode D5 coupled in parallel with the resistor R4 are additionally provided. On the lead transmitting the control signal DRL, resistors R5 and R6 and a diode D6 coupled in parallel with the resistor R6 are further provided.
The
In the present embodiment, the
Referring to fig. 5, fig. 5 is a schematic view illustrating a projection system according to an embodiment of the invention. The projection system 500 includes a driving device 510, a light emitting device 520, and a lens 530, wherein the light emitting device 520 projects an output light beam to the lens 530. The driving device 510 can be implemented according to the driving
Referring to fig. 6, fig. 6 is a flowchart illustrating a driving method of a light emitting device according to an embodiment of the invention. Step S610 provides a control signal generator to generate a first control signal pair. Step S620 provides a voltage level isolator, wherein the input end circuit of the voltage level isolator receives the first control signal pair, and the output end circuit of the voltage level isolator generates the second control signal pair according to the first control signal pair, wherein the voltage tolerance of the output end circuit is higher than that of the input end circuit. Step S630 provides the power converter to convert the first power according to the second control signal pair to generate the second power, and provides the second power to drive the light emitting device.
The details of the above steps are given in the above embodiments and implementations, and are not repeated herein.
In summary, the embodiments of the invention utilize the voltage level isolator to isolate the control signal generator of the low voltage system and the power converter of the high voltage system. Therefore, when the voltage value of the power received by the power converter is increased, the driving device can keep normal operation, and the cost of the circuit is kept from increasing.
However, the above description is only a preferred embodiment of the present invention, and the scope of the present invention should not be limited thereby, and all the simple equivalent changes and modifications made by the claims and the contents of the specification of the present invention are still included in the scope covered by the present invention. Furthermore, it is not necessary for any embodiment or claim of the invention to address all of the objects, advantages, or features disclosed herein. In addition, the abstract and the title are provided to assist the patent document searching and are not intended to limit the scope of the invention. Furthermore, the terms "first," "second," and the like in the description or in the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used for limiting an upper limit or a lower limit on the number of components.
[ notation ] to show
100. 400, 510: drive device
110. 410: control signal generator
120. 300, 420: voltage level isolator
121: input terminal circuit
122: output terminal circuit
130. 200: power converter
140. 440, 520: light emitting device
500: projection system
530: lens barrel
CTH, CTL, DRH, DRL: control signal
Vin, Vout, VDD2, VC1, VC 2: power supply
T1, T2: transistor with a metal gate electrode
L1: inductance
C1~C7、C21、C BOOT: capacitor with a capacitor element
DBOOT, D1-D6: diode with a high-voltage source
R1-R6: resistance (RC)
SW: center end
GND, GND1, GND 2: reference ground
BUF1, BUF 2: buffer device
330: quasi-position shifter
350: undervoltage locking circuit
340: logic arithmetic unit
BCTH, BCTL: buffering signals
LV1, LV 2: voltage offset signal
VDD 1: pull-up power supply
UVLO: locking signal
A1, A2: signal
LED 1-LEDN: light emitting diode
LB: light beam
S610 to S630: and a step of driving the light emitting device.
- 上一篇:一种医用注射器针头装配设备
- 下一篇:一种无频闪发光二极管驱动装置及线性稳压方法