POWER CONVERTERS AND E-PAPER DEVICES USING THE SAME
A display device including an e-paper device and a power converter is provided. The e-paper device displays information. The power converter generates a plurality of output voltages respectively at a plurality of output terminals and provides the plurality of output voltages to the e-paper device. The power converter includes a transformer and a plurality of diodes. The transformer has a primary winding and a plurality of secondary windings. The diodes are electrically connected between the secondary windings and the output terminals for generating the output voltages, respectively.
The present application claims the benefit of U.S. provisional application entitled “POWER CONVERTERS AND E-PAPER DEVICES USING THE SAME”, Ser. No. 61/250,304, filed Oct. 9, 2009.
BACKGROUND OF THE INVENTION1. Field of the Invention
The invention relates to a power converter providing a plurality of output voltages, and more particularly to an e-paper device which uses a power converter providing a plurality of output voltages.
2. Description of the Related Art
Recently, e-paper devices have been developed. Since power consumption of e-paper devices is very low, e-paper devices can be applied in mobile display devices using batteries. Power converters which drive e-paper devices are requested to have high voltage, low current, and high conversion efficiency characteristics and are requested to provide multiple output voltages. Thus, to achieve the objective of providing multi output voltages by the boost power converters, a power converter having a plurality of boost power converters 1, as shown in
Thus, it is desired to provide a power converter which provides a plurality of output voltages and has high work efficiency.
BRIEF SUMMARY OF THE INVENTIONAn exemplary embodiment of a display device includes an e-paper device and a power converter. The e-paper device displays information. The power converter generates a plurality of output voltages respectively at a plurality of output terminals and provides the plurality of output voltages to the e-paper device. The power converter includes a transformer and a plurality of diodes. The transformer has a primary winding and a plurality of secondary windings. The diodes are electrically connected between the secondary windings and the output terminals to generate the output voltages, respectively.
Another exemplary embodiment of a display device includes an e-paper device and a power converter. The e-paper device displays information. The power converter generates a plurality of output voltages respectively at a plurality of output terminals and provides the output voltages to the e-paper device. The power converter includes a transformer, at least one first diode, and at least one second diode. The transformer has a primary winding and at least one secondary winding. The first diode is electrically connected between the primary winding and one of the output terminals for generating the corresponding output voltage. The second diode is electrically connected between the at least one secondary winding and one of the output terminals to generate the corresponding output voltage.
An exemplary embodiment of a power converter generates a plurality of output voltages and includes a plurality of output terminals, a transformer, at least one first diode, and at least one second diode. The output terminals respectively provide the output voltages. The transformer has a primary winding and at least one secondary winding. The first diode is electrically connected between the primary winding and one of the output terminals to generate the corresponding output voltage. The second diode is electrically connected between the at least one secondary winding and one of the output terminals to generate the corresponding output voltage.
Another exemplary embodiment of a display device comprises an e-paper device and a power converter. The e-paper device displays information. The power generates a plurality of output voltages respectively at a plurality of output terminals and provides the output voltages to the e-paper device. The power converter comprises a coupled-inductor, a first diode, and a second diode. The coupled-inductor has a first winding and a second winding. The first winding and the second winding are electrically connected in series between a first node and a second node. The first diode is electrically connected between a joint of the first winding and the second winding and one of the output terminals to generate the corresponding output voltage. The second diode is electrically connected between the second node and one of the output terminals to generate the corresponding output voltage.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
In the embodiment of
Each of the secondary windings Ns1 and Ns2 has a first terminal and a second terminal. The diode 44 is electrically connected between the first terminal of the secondary winding Ns1 and the output terminal OUT1. The second terminal of the secondary winding Ns1 is electrically connected to the ground terminal GND. The diode 45 is electrically connected between the first terminal of the secondary winding Ns2 and the output terminal OUT2. The second terminal of the secondary winding Ns2 is electrically connected to the ground terminal GND. The capacitor 46 is electrically connected to the output terminal OUT1 and the ground terminal GND, and the capacitor 47 is electrically connected to the output terminal OUT2 and the ground terminal GND. The generation of the output voltages Vout1 and Vout2 will be described in following.
Referring to
According to the above embodiment of
In the embodiment of
In the embodiment of
In other some embodiments, the second terminal of the secondary winding Ns1 is electrically connected to the output terminal OUT2 instead of the ground terminal GND, as shown in
According to the embodiment of
In the embodiment of
The control unit 80 does not detect the output voltage Vout1, but the control unit 80 is used to detect the output voltage Vout3 instead. As shown in
In the embodiment of
In the embodiment of
The diode 94 is electrically connected between the node N91 and the output terminal OUT1. The diode 95 is electrically connected between the joint N92 and the output terminal OUT2. The capacitor 96 is electrically connected to the output terminal OUT1 and the ground terminal GND, and the capacitor 97 is electrically connected to the output terminal OUT2 and the ground terminal GND. The generation of the output voltages Vout1 and Vout2 will be described in following.
Referring to
According to the above embodiment of
In the embodiment of
While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Claims
1. A display device comprising:
- an e-paper device for displaying information; and
- a power converter for generating a plurality of output voltages respectively at a plurality of output terminals and providing the output voltages to the e-paper device, wherein the power converter comprises: a transformer having a primary winding and a plurality of secondary windings; and a plurality of diodes electrically connected between the secondary windings and the output terminals for generating the output voltages, respectively.
2. The display device as claimed in claim 1, wherein the power converter further comprises:
- a power source electrically connected between a first terminal of the primary winding and a ground terminal;
- a control unit for detecting at least one output voltage and providing a control signal according to the at least one output voltage; and
- a switch electrically connected between a second terminal of the primary winding and the ground terminal and controlled by the control signal.
3. The display device as claimed in claim 2, wherein the control signal is a pulse width modulation (PWM) signal.
4. The display device as claimed in claim 1, wherein each of the secondary windings has a first terminal respectively electrically connected to one of the output terminals through the corresponding diode and a second terminal.
5. The display device as claimed in claim 4, wherein the second terminal of at least one of the secondary windings is electrically connected to a ground terminal.
6. The display device as claimed in claim 4, wherein the second terminal of at least one of the secondary windings is electrically connected to the first terminal of at least one of the other secondary windings.
7. The display device as claimed in claim 4, wherein the second terminal of at least one of the secondary windings is electrically connected to the output terminal corresponding to at least one of the other secondary windings.
8. The display device as claimed in claim 1, wherein the power converter further comprises at least one regulation unit electrically connected between one of the diode and the corresponding output terminal for regulating the corresponding output voltage.
9. A display device comprising:
- an e-paper device for displaying information; and
- a power converter for generating a plurality of output voltages respectively at a plurality of output terminals and providing the output voltages to the e-paper device, wherein the power converter comprises: a transformer having a primary winding and at least one secondary winding; at least one first diode electrically connected between the primary winding and one of the output terminals for generating the corresponding output voltage; and at least one second diode electrically connected between the at least one secondary winding and one of the output terminals for generating the corresponding output voltage.
10. The display device as claimed in claim 9, wherein the power converter further comprises:
- a power source electrically connected between a first terminal of the primary winding and a ground terminal;
- control unit for detecting at least one output voltage and providing a control signal according to the at least one output voltage; and
- a switch electrically connected between a second terminal of the primary winding and the ground terminal and controlled by the control signal.
11. The display device as claimed in claim 10, wherein the control signal is a pulse width modulation (PWM) signal.
12. The display device as claimed in claim 9, wherein the at least one secondary winding has a first terminal electrically connected to one of the output terminals through the corresponding second diode and a second terminal.
13. The display device as claimed in claim 12, wherein the second terminal of the at least one secondary winding is electrically connected to a ground terminal.
14. The display device as claimed in claim 12, wherein the transformer has a first secondary winding and a second secondary winding, and the second terminal of the first secondary winding is electrically connected to the first terminal of the second secondary winding.
15. The display device as claimed in claim 12, wherein the transformer has a first secondary winding and a second secondary winding, and the second terminal of the first secondary winding is electrically connected to the output terminal corresponding to the second secondary winding.
16. The display device as claimed in claim 8, wherein the power converter further comprises at least one regulation unit electrically connected between the at least one second diode and the corresponding output terminal for regulating the corresponding output voltage.
17. A power converter for generating a plurality of output voltages comprising:
- a plurality of output terminals for respectively providing the output voltages;
- transformer having a primary winding and at least one secondary winding;
- at least one first diode electrically connected between the primary winding and one of the output terminals for generating the corresponding output voltage; and
- at least one second diode electrically connected between the at least one secondary winding and one of the output terminals for generating the corresponding output voltage.
18. The power converter as claimed in claim 17 further comprising:
- a power source electrically connected between a first terminal of the primary winding and a ground terminal;
- a control unit for detecting at least one output voltage and providing a control signal according to the at least one output voltage; and
- a switch electrically connected between a second terminal of the primary winding and the ground terminal and controlled by the control signal.
19. The power converter as claimed in claim 17, wherein the control signal is a pulse width modulation (PWM) signal.
20. The power converter as claimed in claim 17, wherein the at least one secondary windings has a first terminal electrically connected to one of the output terminals through the corresponding second diode and a second terminal.
21. The power converter as claimed in claim 20, wherein the second terminal of the at least one secondary winding is electrically connected to a ground terminal.
22. The power converter as claimed in claim 20, wherein the transformer has a first secondary winding and a second secondary winding, and the second terminal of the first secondary winding is electrically connected to the first terminal of the second secondary winding.
23. The power converter as claimed in claim 20, wherein the transformer has a first secondary winding and a second secondary winding, and the second terminal of first secondary winding is electrically connected to the output terminal corresponding to the second secondary winding.
24. The power converter as claimed in claim 17 further comprising at least one regulation unit electrically connected between the at least one second diode and the corresponding output terminal for regulating the corresponding output voltage.
25. A display device comprising:
- an e-paper device for displaying information; and
- a power converter for generating a plurality of output voltages respectively at a plurality of output terminals and providing the output voltages to the e-paper device, wherein the power converter comprises: a coupled-inductor having a first winding and a second winding, wherein the first winding and the second winding are electrically connected in series between a first node and a second node; a first diode electrically connected between a joint of the first winding and the second winding and one of the output terminals for generating the corresponding output voltage; and a second diode electrically connected between the second node and one of the output terminals for generating the corresponding output voltage.
26. The display device as claimed in claim 25 further comprising:
- a power source electrically connected between a first node and a ground terminal;
- a control unit for detecting at least one output voltage and providing a control signal according to the at least one output voltage; and
- a switch electrically connected between the join and the ground and controlled by the control signal.
Type: Application
Filed: Oct 12, 2010
Publication Date: Apr 14, 2011
Inventors: Ming-Chih Chiu (Taoyuan Hsien), Wen-Pin Liu (Taoyuan Hsien), Rong Hsu (Taoyuan Hsien)
Application Number: 12/902,694
International Classification: G09G 5/00 (20060101); H02M 3/335 (20060101);