Patent Application
20130230318
This application claims the priority of Korean Patent Application No. 10-2012-0022377 filed on Mar. 5, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an interface apparatus and a method of operating the same able to facilitate rapid and efficient data communications transmissions, of a display having a high degree of freedom in terms of hardware design.
2. Description of the Related Art
Display apparatuses applied to electronic devices such as mobile electronic devices and the like, are required to process composite signals, such as image data signals transmitted from a central processing unit (CPU) of an electronic device, power signals, touch sensing signals detected from a touch screen, signals sensed by an image sensor, or the like. To this end, a method of transmitting an 8 bit or larger signal through two differential lines by a low voltage differential signaling (LVDS) mechanism has been proposed. However, the above-mentioned method also requires a connection line for additional control.
Meanwhile, with regard to a mechanism for processing a high-speed, large-capacity data transmission between the display and the central processing unit (CPU) in a mobile device at low power, a mobile industry processor interface (MIPI) standard has been proposed. In the MIPI-compliant transmission mechanism, a transmission rate of 850 Mbps may be implemented through a single lane using a high speed (HS) mode and a low power (LP) mode, and a maximum bit rate of 3.2 Gbps may be supported, in particular, when using four lanes.
The MIPI-compliant transmission mechanism serializes pieces of data included in a signal output in parallel so as to comply with the MIPI standard, transmits the serialized data, and then, once more de-serializes the received data, thereby reconstituting the data to form an image. However, even when transmitting a signal including the large-capacity image data using the MIPI standard, the display device is connected to the CPU by a general conductor line (generally formed of copper) and as a result, design restrictions may be increased, while the occurrence of electromagnetic interference (EMI) and signal loss over distance may be increased.
In the following Patent Documents 1 and 2, Patent Document 1 relates to a method of controlling multi-level communications between a communications bus and devices, which discloses controlling a level of a plurality of signals having compatibility and transmitting and receiving the controlled signal, while Patent Document 2 relates to a display interface system, which discloses transmitting and receiving a data signal or a clock signal through a plurality of channels.
An aspect of the present invention provides a communications interface apparatus and a method of operating the same, capable of reducing limitations on hardware design and significantly reducing signal loss over distance by transmitting a plurality of data signals having different levels or frequencies through a transmission line formed by combining a plastic optical fiber with a conductor line and transmitting high-capacity data through the plastic optical fiber.
According to an aspect of the present invention, there is provided a communications interface apparatus, including: a transmission line including a conductor line and a plastic optical fiber for optical communications; a signal transmitting unit transmitting a first data signal through the plastic optical fiber and transmitting a second data signal through the conductor line; and a signal receiving unit receiving the first data signal and the second data signal, wherein the signal transmitting unit differentiates a signal as the first data signal or the second data signal based on at least one of a level and a frequency of the signal to be transmitted.
The signal transmitting unit may include: a signal converting unit generating the first data signal by serializing original data provided in parallel and generating the second data signal transmitted in a low power mode from part of the data provided in parallel; and an optical output unit outputting the first data signal to the plastic optical fiber.
The signal converting unit may include: a repeater block filtering the original data; a serializer serializing an output of the repeater block; and a driving circuit unit generating the first data signal transmitted in a high speed mode from an output of the serializer.
The signal receiving unit may include: an optical signal detector receiving the first data signal from the plastic optical fiber; a de-serializer de-serializing the first data signal to realign a plurality of pieces of data included in the first data signal in parallel; and an electrical signal detector receiving the second data signal transmitted in the low power mode.
The optical signal detector may include: a photo diode converting the first data signal into a current signal; and an amplifier converting the current signal into a voltage signal having a logic level.
The de-serializer may include a clock data recovering circuit recovering a clock signal from the first data signal.
A swing level width of the first data signal may be smaller than that of the second data signal.
According to another aspect of the present invention, there is provided a method of operating a communications interface apparatus, including: generating a first data signal by serializing original data provided in parallel through a plurality of lanes and generating a second data signal from at least a part of the original data; transmitting the first data signal through a plastic optical fiber and transmitting the second data signal through a conductor line; and recovering the original data by receiving the first data signal and the second data signal, wherein at least one of a level and a frequency of the first data signal and the second data signal is different from each other.
In the generating of the signals, the first data signal may be generated from data of an image displayed by a display device and the second data signal may be generated from at least one of a power signal of the display device and a sensing signal of a touch screen panel provided in the display device.
In the generating of the signals, the first data signal and the second data signal maybe generated so that a swing level width of the first data signal has a larger value than that of the second data signal.
In the transmitting, the first data signal may be transmitted in a high speed mode and the second data signal may be transmitted in a low power mode.
The second data signal may include a control code for starting an operation to receive the first data signal in the high speed mode.
The recovering may include: generating clock data from the first data signal; generating the original data from the first data signal; and de-multiplexing the original data in each of the plurality of lanes connected to one another in parallel based on the clock data.
The generating of the original data may include: converting the first data signal into a current signal; generating a voltage signal having a logic level from the current signal; and generating the original data by de-serializing the voltage signal.
The transmitting may include: filtering the original data; and generating the first data signal by serializing the filtered original data.
The above and other aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Embodiments of the present invention will hereinafter be described in detail with reference to the accompanying drawings. These embodiments will be described in detail in order to allow those skilled in the art to practice the present invention. It should be appreciated that various embodiments of the present invention are different but do not have to be exclusive. For example, specific shapes, configurations, and characteristics described in an embodiment of the present invention may be implemented in another embodiment without departing from the spirit and the scope of the present invention. In addition, it should be understood that position and arrangement of individual components in each disclosed embodiment may be changed without departing from the spirit and the scope of the present invention. Therefore, a detailed description described below should not be construed as being restrictive. In addition, the scope of the present invention is defined only by the accompanying claims and their equivalents if appropriate. Similar reference numerals will be used to describe the same or similar functions throughout the accompanying drawing.
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily practice the present invention.
Referring to
When the display device 130 communicates with the central processing unit of the mobile device 100 by using a general flexible printed circuit board (FPCB) on which conductive patterns formed of a metal such as copper (Cu), or the like, are formed, it may be difficult to apply the display device 130 rotating or tilted in several directions due to a restriction of a design. Further, a plurality of flexible printed circuit boards are required to transmit a power signal, a data signal, a control signal, or the like, for the display device 130 and the touch screen device, and as a result, design complexity may be increased, signal loss may occur, and problems such as electromagnetic interference (EMI), or the like, in response to the increased transmission path due to the characteristics of the conductive pattern may also occur.
Therefore, as the transmission line of the communications interface apparatus 140 according to the embodiment of the present invention, a hybrid plastic of fiber (POF) using both of the optical cable line and the conductor line formed of a metal such as copper (Cu), or the like, may be applied. In this case, the high-capacity image data, or the like, displayed by the display device 130 is transmitted through the optical cable line which can implement fast data transmission, and a touch sensing data, a power signal, or the like, generated from the touch screen device may be transmitted through the conductor line having a slow speed but small power consumption.
Referring to
As described above, the transmission line 210 may include a plastic optical fiber (POF) 213 and a conductor line 215. For example, in the transmission line 210 having a cylindrical cross section, the plastic optical fiber 213 may be disposed in a center thereof and a plurality of conductor lines 215 may be disposed at a circumference thereof. The conductor lines 215 are surrounded by an outer jacket 217 to protect against external impacts, the introduction of dust, or the like.
The signal transmitting unit 220 receives a piece of data to be transmitted from the first circuit unit 230 and transmits the data through the transmission line 210. For example, the signal transmitting unit 220 may serialize an amount of portion of original data received from the first circuit unit 230 to generate a first data signal transmitted through the plastic optical fiber 213. Part of the original data received from the first circuit unit 230 maybe separately processed as a second data signal transmitted through the conductor line 215. In order to generate the first data signal transmitted through the plastic optical fiber 213, the signal transmitting unit 220 may include a serializer. That is, the original data provided in parallel by the first circuit unit 230 may be serialized by a serializer and be converted into the first data signal appropriate for optical communications.
The signal receiving unit 240 may de-serialize the first data signal serialized by the signal transmitting unit 220 and transmitted through the plastic optical fiber 213 to recover the original data and may provide the original data to the second circuit unit 250 in parallel. The second data signal which may be separately processed rather than being serialized by the signal transmitting unit 220 is received through the conductor line 215 and is transmitted to the second circuit unit 250. For the signal processing and data recovering operation as described above, the signal receiving unit 240 may include a de-serializer and a clock data recover (CDR) circuit for extracting a clock signal from the first data signal.
The first data signal transmitted through the plastic optical fiber 213 and the second data signal transmitted through the conductor line 215 may have different values in terms of at least one of a level and a frequency. The plastic optical fiber 213 consumes a large amount of power in transmitting a piece of data at a higher speed than the conductor line 215. The conductor line 215 cannot easily implement the high-speed data transmission, but has low power consumption. Therefore, a balance between the power consumption and the signal transmission rates may be controlled by generating the first data signal from the high-capacity data of image displayed by the display device 130 and generating the second data signal from the power signal, the sensing data of the touch screen device, or the like.
Referring to
The first circuit unit 230 provides the original data to the signal converting unit 300 in parallel communications. The original data provided in parallel is amplified by the repeater 310 and the serializer 320 may serialize the amplified original data to convert the serialized original data into the first data signal that maybe transmitted to the single plastic optical fiber 213. In
The converter 340 included in the signal converting unit 300 may use at least a part of the original data to generate the second data signal transmitted through the conductor line 215 in a low power (LP) mode. The second data signal may include the data transmitted through the conductor line 215 at low power and low speed. For example, the second data signal may include the power signal of the display device 130, the touch screen device, or the like, the sensing data of the touch screen device, or the like.
In addition, for efficiency of power management, the second data signal transmitted in the low power mode may include information that may indicate whether the detection operation of the first data signal transmitted in the high speed mode starts. For example, as shown in
Referring to
The voltage signal output by the optical signal detector 440 is transmitted to the signal recovery unit 400. The signal recovery unit 400 may include a clock data recovery circuit 410, a de-serializer 420, and electrical signal detector 430. The clock data recovery circuit 410 recovers the clock data from the voltage signal output by the optical signal detector 440. In
The electrical signal detector 430 receives the second data signal transmitted through the conductor line 215 in the low power mode and detects the power signal, the control signal, or the like, therefrom. The control signal may include the information regarding an operation switching timing that receives and processes the first data signal transmitted in the high speed mode by the signal receiving mode 240. For example, as described above, when the digital logic values of LP+ and LP− are consecutively changed from [11] to [00] via [01], the operation mode of the signal receiving unit 240 maybe switched to the high speed mode that receives and processes the first data signal. In addition, the electrical signal detector 430 may detect an instruction language necessary to recover the image data, or the like, from the second data signal.
Referring to
The first data signal and the second data signal generated in S50 are transmitted to the signal receiving unit 240 through the plastic optical fiber 213 and the conductor line 215 (S52). The first data signal transmitted in the high speed mode through the plastic optical fiber 213 is a data signal generated by serializing the original data provided in parallel through the plurality of lanes, such that the signal receiving unit 240 also needs to be operated in the high speed mode so as to allow the signal receiving unit 240 to recover the original data from the first data signal. Therefore, whether the signal receiving unit 240 is operated in the high speed mode and information for clock synchronization in the high speed mode may be transmitted by being included in the second data signal. This will be described in detail with reference to
Describing the change in the second data signals 610 and 615 transmitted in the low power mode, both values of the LP+ and the LP− are changed to LP−01 in which the LP+ has GND corresponding to the digital logic value 0, from LP−11 that is a state having VDD corresponding to a digital logic value 1. Next, when the value of the LP− is also changed to the GND and thus, the state of the second data signal reaches LP-00, the signal receiving unit 240 is switched to the high speed mode to prepare to receive and recover the first data signal 620. That is, when detecting that a combination of the digital logic values of the LP+ 615 and the LP− 610 transmitted by being included in the second data signals 610 and 615 is changed from [11] to [00] via [01], the signal receiving unit 240 may be operated in the high speed mode.
Referring to
When the first data signal 620 and the second data signals 610 and 615 are transmitted, as described with reference to
The communications interface apparatus and the method of operating the same described with reference to
As set forth above, according to embodiments of the present invention, in the communications interface apparatus and the method of operating the same between the display device and the central processing unit, data signals having different levels or frequencies may be transmitted and received through the transmission line including the plastic optical fiber and the conductor line. Therefore, signal loss may be reduced by transmitting and receiving the high-capacity data through the plastic optical fiber at a relatively high speed, and more various types of hardware design structures than the case of using the general FPCB may be provided.
While the present invention has been shown and described in connection with the embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2012-0022377 | Mar 2012 | KR | national |
