DRIVING CIRCUIT AND RELATED DRIVING METHOD
20220262300 · 2022-08-18
Inventors
- Chih-Hao HUNG (HSIN-CHU, TW)
- Hung-Chi WANG (HSIN-CHU, TW)
- Ya-Fang CHEN (HSIN-CHU, TW)
- Chih-Hsiang YANG (HSIN-CHU, TW)
Cpc classification
G09G2310/08
PHYSICS
G09G2320/0666
PHYSICS
G09G2370/08
PHYSICS
G09G3/2096
PHYSICS
G09G2300/06
PHYSICS
G09G3/2014
PHYSICS
International classification
G09G3/20
PHYSICS
Abstract
A driving circuit for a display panel and including a receiving interface, a timing controller, a pulse width modulation controller and a line latch is disclosed. The receiving interface is configured to receive a first input signal, a second input signal and a link signal to generate a plurality of display data accordingly, wherein the first input signal and the second input signal are a pair of differential signals. The timing controller is configured to interpret the first input signal, the second input signal and the link signal to generate a trigger signal. The pulse width modulation controller is configured to perform pulse width modulation to generate a first output signal and a second output signal. The line latch is configured to hold the first and second output signals, and output the first and second output signals according to the trigger signal to drive the display panel.
Claims
1. A driving circuit for a display panel, comprising: a receiving interface configured to receive a first input signal, a second input signal and a link signal to generate a plurality of display data, wherein the first input signal and the second input signal are a pair of differential signals; a timing controller configured to receive the first input signal, the second input signal, and the link signal through the receiving interface, and interpret the first input signal, the second input signal, and the link signal to generate a trigger signal; a pulse width modulation controller coupled to the timing controller to perform pulse width modulation according to the trigger signal and the plurality of display data to generate a first output signal and a second output signal; and a line latch coupled to the pulse width modulation controller to hold the first output signal and the second output signal temporarily, and output the first output signal and the second output signal to drive the display panel according to the trigger signal.
2. The driving circuit of claim 1, comprising: a configuration register coupled to the receiving interface to store an output current parameter; a rectifier coupled to the configuration register to generate an output current according to the output current parameter; and a plurality of current sources coupled to the rectifier and the pulse width modulation controller to generate a plurality of driving currents to the pulse width modulation controller according to the output current.
3. The driving circuit of claim 1, wherein the link signal is a bidirectional control signal or a unidirectional control signal.
4. The driving circuit of claim 2, wherein the output current parameter is gray scale mode, scanning mode, or color parameters.
5. The driving circuit of claim 2, further comprising a resistor configured to control the output current.
6. The driving circuit of claim 1, wherein the driving circuit is utilized in a driving module, and the driving module comprises: an input/output interface configured to receive a plurality of first input signals, a plurality of second input signals and the link signal from a signal input source simultaneously; and a plurality of drive circuits connected in parallel with the input/output interface; wherein the input/output interface transmits the link signal, the plurality of first input signals, and the plurality of second input signals to the plurality of driving circuits in parallel.
7. The driving circuit of claim 6, wherein the driving module comprises a circuit board, and the input/output interface and the plurality of driving circuits are located on the circuit board, or the plurality of driving circuits are located on the circuit board and the input/output interface is located on another circuit board.
8. The driving circuit of claim 1, wherein the driving circuit is utilized in a driving module, and the driving module comprises: an input/output interface configured to receive the first input signal, the second input signal, and the link signal from a signal input source, wherein the first input signal includes a plurality of first input signals, and the second input signal includes a plurality of second input signals; and a plurality of driving circuits connected to the input/output interface in series; wherein the input/output interface sequentially transmits the link signal, the plurality of first input signals, and the plurality of second input signals to the plurality of driving circuits.
9. The driving circuit of claim 8, wherein the driving module comprises a circuit board, and the input/output interface and the plurality of driving circuits are located on the circuit board, or the plurality of driving circuits are located on the circuit board and the input/output interface is located on another circuit board.
10. The driving circuit of claim 1, wherein the driving circuit is utilized in a driving module, and the driving module comprises a scan switch circuit, the scan switch circuit and the driving circuit are integrated on a same integrated circuit chip.
11. The driving circuit of claim 8, wherein the display panel is a common anode passive matrix light-emitting diode panel, the scan switch circuit includes a plurality of P-type transistor switch.
12. The driving circuit of claim 8, wherein the display panel is a common cathode passive matrix light-emitting diode panel, the scan switch circuit includes a plurality of N-type transistor switches.
13. A driving method, utilized for driving a display device, comprising: receiving a first input signal, a second input signal and a link signal with a receiving interface to generate a plurality of display data, wherein the first input signal and the second input signal are a pair of differential signals; interpreting the first input signal, the second input signal and the link signal with a timing controller to generate a trigger signal; performing pulse width modulation with a pulse width modulation controller according to the trigger signal and the plurality of display data to generate a first output signal and a second output signal; and holding the first output signal and the second output signal with a line latch temporarily, and outputting the first output signal and the second output signal according to the trigger signal to drive the display panel.
14. The driving method of claim 13, further comprising: storing an output current parameter with a configuration register; generating an output current with a rectifier according to the output current parameter; and generating a plurality of driving current with a plurality of current sources to the pulse width modulation controller according to the output current.
15. The driving method of claim 13, further comprising displaying an image according to the first output signal and the second output signal.
16. The driving method of claim 13, wherein the link signal is a bidirectional control signal or a unidirectional control signal.
17. The driving method of claim 14, wherein the output current parameter is gray scale mode, scanning mode, or color parameters.
18. The driving method of claim 14, further comprising controlling the output current with a resistor.
19. The driving method of claim 13, further comprising: receiving a plurality of first input signals, a plurality of second input signals and the link signal from a signal input source simultaneously with an input/output interface; and transmitting the link signal, the plurality of first input signals and the plurality of second input signals to a plurality of driving circuits in parallel with the input/output interface, wherein the plurality of driving circuits are connected in parallel with the input/output interface.
20. The driving method of claim 13, further comprising: receiving the first input signal, the second input signal and the link signal from a signal input source with an input/output interface, wherein the first input signal includes a plurality of first input signals, and the second input signal includes a plurality of second input signals; and transmitting the link signal, the plurality of first input signals and the plurality of second input signals to a plurality of driving circuits, wherein the plurality of driving circuits and the input/output interface are connected in series with each other.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures.
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
DETAILED DESCRIPTION
[0022] In following disclosure, when a component is called “connect” or “couple”, it can refer to “electrically connect” or “electrically couple”. “Connect” or “couple” can also be used to indicate the coordinated operation or interaction between two or more components. In addition, although terms such as “first”, “second”, etc. are used herein to describe different elements, the terms are only used to distinguish elements or operations described in the same technical terms. Unless the context clearly indicates, the terms do not specifically refer to or imply the order or sequence, nor are they used to limit the present disclosure.
[0023]
[0024] In operation, the scan switch circuit 12 includes M switches for providing a driving voltage VLED to the display panel 14 according to the M scan signals SC[1]-SC[M]. The driving circuit 10 is configured to provide an output signal SDO (drawn in
[0025]
[0026] In operation, the scan switch circuit 22 includes M switches for coupling the display panel 24 to a ground voltage GND according to the M scan signals SC[1]-SC[M]. The driving circuit 20 is configured to provide an output signal SDO (drawn in
[0027]
[0028]
[0029] The architecture of the driving circuit 10 is shown in
[0030]
[0031] It is noted that, the driving circuit 40 in
[0032]
[0033] The receiving interface 61 is coupled to the timing controller 62, the configuration register 63 and the line latch 64 for receiving a first input signal SDI_P, a second input signal SDI_N and a link signal LK, according to which multiple display data D[1]-D[N] are generated. The link signal LK is a signal for communication between the driving circuit 60 and an input signal source (such as a processor), and the link signal LK may be a bidirectional or unidirectional control signal. The timing controller 62 is coupled to the receiving interface 61 and the pulse width modulation controller 66 for receiving the first input signal SDI_P, the second input signal SDI_N, and the link signal LK with the receiving interface 61, and the interprets first input signal SDI_P, the second input signal SDI_N and the link signal LK, to generate a trigger signal STB to the pulse width modulation controller 66. The configuration register 63 is coupled to the receiving interface 61 for storing at least one configuration parameter, such as but not limited to an output current parameter RINT, gray scale mode, scanning mode, and color parameters, etc. The rectifier 65 is coupled to the configuration register 63 and multiple current sources CS1-CSN, and is configured to generate an output current I.sub.out to the current sources CS1-CSN according to an output current parameter RINT. The current sources CS1-CSN are coupled to the rectifier 65 and the pulse width modulation controller 66, and are configured to generate multiple driving currents to the pulse width modulation controller 66 for the multiple channels CH1-CHN according to the output current I.sub.out. The pulse width modulation controller 66 is coupled to the timing controller 62 and the line latch 64, and is configured to perform pulse width modulation according to the trigger signal STB and multiple display data D[1]-D[N] corresponding to the channels CH1-CHN, to generate a first output signal SDO_P and a second output signal SDO_N. The line latch 64 is coupled to the receiving interface 61 and the pulse width modulation controller 66 to temporarily hold the first output signal SDO_P and the second output signal SDO_N, and output the first output signal SDO_P and the second output signal SDO_N according to the trigger signal STB.
[0034] It is noted that, in the disclosed embodiment, the first input signal SDI_P and the second input signal SDI_N are a differential pair of signal configured to replace the single-wired input signal SDI in
[0035] Further, since the differential signal has the features of strong anti-interference ability and accurate timing positioning, signal distortion can be avoided, and no additional clock signal (such as the data clock signal DCLK) needs to be referred to. The timing controller 62 can reconstruct (or generate) related timing signals (such as the trigger signal STB) according to the first input signal SDI_P and the second input signal SDI_N, thus the driving circuit 60 does not need to receive additional gray-scale clock signals GCLK and trigger signal ROW. In addition, under the premise that the application range of the display panel is known, the resistor configured to control the output current I.sub.out (resistance value REXT) can be integrated in the drive circuit 60, and the output current I.sub.out can be set with the output current parameter RINT. In this way, it may be seen from
[0036]
[0037]
[0038] In operation, the input/output interface 89 may simultaneously receive the first input signals D1_P-D8_P, the second input signals D1_N-D8_N and the link signal LK from a signal input source, transmit the link signal LK to the driving circuits 81-88 for communication, and simultaneously transmit the first input signals D1_P-D8_P and the second input signals D1_N-D8_N to the driving circuits 81-88 in parallel. In this way, the present disclosure may realize parallel transmission, and the data rate per unit time may be multiples (for example, eight times) of the data rate of single point transmission.
[0039]
[0040] In operation, the input/output interface 99 may receive the link signal LK, the first input signal D_P, and the second input signal D_N from a signal input source. The input/output interface 99 communicates with the driving circuits 91-98 with the link signal LK. For example, the upstream signal source informs the downstream receiving end to receive display data with the link signal LK, thus the driving circuits 91-98 sequentially receive the first input signal D1_P-D8_P and the second input signal D1_N-D8_N. In this way, the present disclosure may realize cascade transmission, and the signal transmission path in the driving module 90 is the shortest, which simplifies the circuit design and avoids signal distortion. Those skilled in the art can select the number of serially connected drive circuits according to actual applications to achieve the optimization of data rate and circuit board layout.
[0041] In the embodiments shown in
[0042]
[0043] Step 101: Receive a first input signal, a second input signal, and a link signal, wherein the first input signal and the second input signal are a pair of differential signals.
[0044] Step 102: Generate a trigger signal according to the first input signal, the second input signal and the link signal.
[0045] Step 103: Perform pulse width modulation according to the first input signal, the second input signal and the trigger signal to generate a first output signal and a second output signal, wherein the first output signal and the second output signal are a pair of differential signals.
[0046] Step 104: Hold the first output signal and the second output signal with the line latch temporarily, and output the first output signal and the second output signal according to the trigger signal.
[0047] In the driving process 100, step 101 may be performed by the receiving interface 61, step 102 may be performed by the timing controller 62, step 103 may be performed by the pulse width modulation controller 66, and step 104 may be performed by the line latch 64. In one embodiment, the driving process 100 further includes generating an output current parameter to a rectifier with a configuration register. Through the driving process 100, the present disclosure may drive the display panel without using random access memory (RAM), which can save circuit area, simplify circuit design, and avoid signal distortion.
[0048] In summary, in the case of using the differential signal of the driving circuit and related driving methods of the present disclosure, the data transmission speed can be effectively increased, thus the driving circuit can support higher resolution and frame rate display panels. There is no need to set up a random access memory (RAM) in the drive circuit to pre-store a large amount of data, thus the area of the drive circuit can be effectively reduced. Because the differential signal has the features of strong anti-interference ability and accurate timing positioning, signal distortion can be avoided, and no additional clock signal needs to be referred to, thus the circuit design can be simplified.
[0049] Also, although the disclosure has been shown and described with respect to one or more implementations, equivalent alterations and modifications will occur to others of ordinary skill in the art based upon a reading and understanding of this specification and the annexed drawings. The disclosure comprises all such modifications and alterations and is limited only by the scope of the following claims. In particular regard to the various functions performed by the above described components (e.g., elements, resources, etc.), the terms used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure. In addition, while a particular feature of the disclosure may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application.