CN102681668B - Low power wireless keyboard - Google Patents
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- CN102681668B CN102681668B CN201210030380.4A CN201210030380A CN102681668B CN 102681668 B CN102681668 B CN 102681668B CN 201210030380 A CN201210030380 A CN 201210030380A CN 102681668 B CN102681668 B CN 102681668B
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention provides a wireless keyboard, which comprises a plurality of keys, a transmitter, an antenna and a controller. The plurality of keys includes a set of keys of a first type and a set of keys of a second type. Each of the plurality of first type keys is associated with one of a plurality of predetermined functions. The controller is configured to receive a first signal from the plurality of keys, the first signal indicating that at least one of the plurality of keys has been selected; determining whether a selected at least one of said plurality of keys is one of said first type of keys; and if the selected at least one of the plurality of keys is one of the first type of keys, activating the transmitter to transmit a second signal via the antenna, wherein the second signal carries information of one of the plurality of predetermined functions associated with the selected at least one of the plurality of keys.
Description
Technical Field
The present invention relates generally to wireless transmissions, and more particularly to a low power wireless keyboard.
Background
Over the past few years, wireless short-range transmission systems have become more common in devices such as remote controls or wireless keyboards. For example, a remote controller or a wireless keyboard typically includes a set of keys, a key matrix, a controller, a transmitter, and a Light Emitting Diode (LED) for transmitting Infrared (IR) signals, or an antenna for transmitting Radio Frequency (RF) signals. For example, fig. 1 is a block diagram of a conventional wireless keyboard 10. Referring to fig. 1, a wireless keyboard 10 may include a set of keys (not shown), a key matrix 11 and a wireless short-range transmission system. The wireless short-range transmission system includes a controller 12, a quartz oscillator 13, a transmitter 14(TX), and an antenna 15. The controller 12 is coupled to the key matrix 11, the quartz oscillator 13 and the transmitter 14. The quartz oscillator 13 is further coupled to the transmitter 14, and the transmitter 14 is further coupled to the antenna 15. The controller 12 may include a modulator 12-1 for generating the modulated signal. In operation, the controller 12 may transmit signals to the key matrix 11 or receive signals from the key matrix 11. For example, the controller 12 is configured to scan the key matrix 11 to find out signals representing "one or more keys are pressed" and to send an activation signal ACT1 and a modulation signal MOD to the quartz oscillator 13 and the transmitter 14, respectively. In response to the enable signal ACT1, the crystal oscillator 13 generates a reference signal REF having a desired frequency and sends the reference signal REF back to the transmitter 14. The transmitter 14 may include a Phase-locked loop (PLL) frequency synthesizer 14-1 and a Power Amplifier (PA) 14-2. The transmitter 14 generates a modulated signal based on the reference signal REF received from the crystal oscillator 13, another enable signal ACT2, and the modulation signal MOD received from the controller 12. The modulated signal is then converted to an RF signal and transmitted via antenna 15.
Fig. 2 is a timing diagram illustrating signals generated by the crystal oscillator 13, the phase-locked loop 14-1, the power amplifier 14-2 and the transmitter 14 after the controller 12 receives a signal representing "one key pressed" from the key matrix 11. First, the controller 12 may start the quartz oscillator 13 to generate the reference signal REF having a desired frequency. Once the crystal oscillator 13 has stabilized, the controller 12 may enable the phase-locked loop frequency synthesizer 14-1 and the power amplifier 14-2. For example, the PLL frequency synthesizer 14-1 may be activated by an activation signal ACT2 to generate a carrier signal based on the frequency of the reference signal REF. Once phase-locked loop frequency synthesizer 14-1 has stabilized, power amplifier 14-2, which receives the carrier signal from phase-locked loop frequency synthesizer 14-1, may be turned "on" or "off" by a modulation signal MOD from controller 12, thereby generating a modulated signal and converting it to an RF signal for transmission via antenna 15.
However, a conventional keyboard having a wireless short-range transmission system operating similar to the above-described one may consume a large amount of power. For example, assume that information is transmitted in 1 Kilobit per second (kbps), and the bit times of the logic high bit and the logic low bit are the same (i.e., the duty cycle is 50%), and the voltages of the logic high bit and the logic low bit are 2 volts (V) and 0V, respectively, and the currents driving the quartz oscillator 13, the phase-locked loop frequency synthesizer 14-1, and the power amplifier 14-2 are 50 microamperes (μ a), 5 milliamperes (mA), and 5 milliamperes, respectively. In addition, for wireless short-range transmission, under the assumption of a very low bit error rate (bit error rate), and in the case that the time length of the phase-locked loop frequency synthesizer locking period is relatively short compared to the time length of the command, the current consumed during the phase-locked loop frequency synthesizer locking period can be ignored. Therefore, the average current for delivering a logic high bit (1) and a logic low bit (0) will be approximately 8000 μ A (i.e., (500 μ A +5mA +5mA) x 0.5+ (500 μ A +5mA) x 0.5). Thus, the energy efficiency will be approximately 16000 nanojoules ("nJ/bit") per bit (i.e., 8000 μ A x 2V/1 kbps). Many energy saving improvements have been proposed in the past by designing different pll frequency synthesizers to produce more energy efficient pll frequency synthesizers (e.g., low power pll frequency synthesizers). However, the phase-locked loop frequency synthesizer 14-1 is continuously on during the entire period that the signal to be transmitted is being generated by the transmitter 14. In other words, the PLL frequency synthesizer 14-1 in the wireless short-range transmission system consumes power during the generation of logic "0" and "1". Thus, the power savings from using a phase-locked loop frequency synthesizer that is energy efficient is still limited. Therefore, there is a need to provide a wireless short-range transmission system, wherein more power can be saved by increasing the data rate and decreasing the operation time of the pll frequency synthesizer while the pll frequency synthesizer is still operating.
In addition, as previously mentioned, wireless short-range transmission systems are commonly used for wireless keyboards. Wireless keyboards typically include two types of keyboards. Each key of the first type is associated with its own function. The first type of key described above includes, for example, text pieces normally arranged in a QWERTY style, function keys (F1, F2, etc.), lock keys, navigation keys (up, down, etc.), and edit keys (delete, enter, etc.), the second type of key is a modifier key that only functions when pressed simultaneously with the other keys, the second type of key includes, for example, Ctrl, Alt, and Shift, e.g., to enter "a", the user will press "Shift" first and then "a", and as shown in fig. 3, in a conventional wireless keyboard, when "Shift" is pressed, the keyboard will transmit the key code of "Shift", and when "a" is pressed, the keyboard will transmit the key code of "a", whereas at the receiver side, e.g., a computer, generally upon receiving the key code of "Shift", no action associated with the display will be performed, because the "Shift" itself has no meaning, the receiver will only receive the command code of "a" An action is performed, for example, the character "A" is displayed on the display. In other words, the "Shift" key transmitted by the wireless keyboard does not provide any meaningful functionality. Therefore, there is a need for a wireless keyboard that saves energy by omitting the transmission of data when only the second type of key (e.g., "Shift") is pressed alone. This power saving is particularly useful for users who are less familiar with typing and who need to press the "Shift" key for a long period of time. Also, for smaller devices, such as palm-type devices, the duration of the user's "Shift" key press may be longer because it may be more difficult to find the correct text key on the small keyboard of the palm-type device. Thus, the ability to save energy in small devices is even more significant and important.
In addition, many conventional keyboards employ Infrared (IR) signaling devices to transmit signals. The amount of current to operate a Light Emitting Diode (LED) light source alone (excluding the current to operate the circuit) typically ranges from 40 to 100 mA. In addition, when using an infrared signaling device for signal transmission, the wireless keyboard needs to be placed in a proper position relative to the receiver because the I R signaling device requires line-of-sight (line-of-sight) operation. It is therefore desirable to provide a wireless keyboard with an environmentally friendly wireless short range transmission system that is capable of transmitting signals at a lower power and does not require line-of-sight operation.
Disclosure of Invention
The present invention is directed to a wireless keyboard to solve the above problems of the prior art.
To achieve the above objective, the present invention provides a wireless keyboard including a plurality of keys, a transmitter, an antenna and a controller. The plurality of keys includes a set of keys of a first type and a set of keys of a second type. Each of the first type of keys is associated with one of a plurality of predetermined functions. The controller is coupled to the plurality of keys and the transmitter. The controller is configured to receive a first signal from the plurality of keys, the first signal indicating that at least one of the plurality of keys has been selected; determining whether a selected at least one of said plurality of keys is one of said first type of keys based on said first signal; and activating the transmitter to transmit a second signal via the antenna if the selected at least one of the plurality of keys is one of the first type of keys. The second signal carries information of one of the plurality of predetermined functions associated with the selected at least one of the plurality of keys.
Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
Drawings
The foregoing summary, as well as the foregoing detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings examples which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
FIG. 1 is a block diagram of a conventional wireless keyboard 10;
FIG. 2 is a timing diagram illustrating signals generated by the quartz oscillator 13, the PLL frequency synthesizer 14-1, the power amplifier 14-2 and the transmitter 14 of the conventional wireless keyboard of FIG. 1;
FIG. 3 is a timing diagram illustrating signals generated by a wireless short-range transmission system of the conventional wireless keyboard of FIG. 1;
fig. 4 is a block diagram of a wireless short-range transmission system 20 according to a first example of the present invention;
FIG. 5 is a timing diagram illustrating the signals generated by the crystal oscillator 13, the PLL frequency synthesizer 24-1, the power amplifier 24-2 and the transmitter 24 shown in FIG. 4;
fig. 6 is a block diagram of a wireless short-range transmission system 30 according to a second example of the present invention;
FIG. 7 is a timing diagram illustrating the signals generated by the crystal oscillator 13, the fast lock phase locked loop frequency synthesizer 34-1, the power amplifier 24-2 and the transmitter 34 shown in FIG. 6;
FIG. 8 is a block diagram of a wireless keyboard 40 according to a third and a fourth exemplary embodiments of the present invention;
FIG. 9 is a flow chart of a method performed by the controller 42 of FIG. 8 for determining whether the conveyor 44 must be activated;
fig. 10 is a timing diagram illustrating the signals received by the controller 42 from the key matrix 11 and the signals transmitted by the transmitter 44 according to the fourth example of the present invention as shown in fig. 8;
FIG. 11 illustrates a process for manufacturing the wireless keyboard shown in FIG. 8;
fig. 12 is a block diagram of a wireless keyboard 50 according to a fifth exemplary embodiment of the present invention;
FIG. 13 is a diagram illustrating an example of the memory 46 shown in FIG. 12 and the relationship between information stored in the memory 46 and the keys on the keyboard;
fig. 14 is a view illustrating a procedure for manufacturing the wireless keyboard shown in fig. 12.
Description of reference numerals: 10: a wireless keyboard; 11: a key matrix; 12: a controller; 12-1: a modulator; 13: a quartz oscillator; 14: a transmitter; 14-1: a phase locked loop frequency synthesizer; 14-2: a power amplifier; 15: an antenna; 20: a wireless short-range transmission system; 22: a controller; 22-1: a modulator; 24: a transmitter; 24-1: a phase locked loop; 24-2: a power amplifier; 24-3: a frequency selection pin; 24-4: a modulation pin; 30: a wireless short-range transmission system; 34: a transmitter; 34-1: fast locking a phase locked loop; 40: a wireless keyboard; 42: a controller; 44: a transmitter; 46: a memory; 50: a wireless keyboard; 52: a controller; t 1: a point in time; t 2: a point in time; t 3: a point in time; 111-115: and (5) carrying out the following steps.
Detailed Description
Reference will now be made in detail to the present examples of the invention as illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. It is noted that the drawings are drawn in simplified form and not to precise scale.
Fig. 4 is a block diagram of a wireless short-range transmission system 20 according to a first embodiment of the present invention. Referring to fig. 4, the wireless short-range transmission system 20 may include a controller 22, a quartz oscillator 13, a transmitter 24 and an antenna 15 for transmitting Radio Frequency (RF) signals. The controller 22 may include a modulator 22-1 and the transmitter 24 may include a Phase Locked Loop (PLL)24-1, a Power Amplifier (PA)24-2, a frequency selection pin 24-3 and one or more modulation pins 24-4. The controller 22 may be a microprocessor or a microcontroller. Modulator 22-1 may include an Amplitude shift keying ("ASK") modulator and an On-off keying ("OOK") modulator. PLL frequency synthesizer 24-1 is an integer-N PLL that may be a digital PLL frequency synthesizer or an analog PLL frequency synthesizer.
In an example according to the present invention, the components of the system 20 may be Integrated in a chip, and the system 20 may be in the form of an Integrated circuit ("IC"). In another example, system 20 may be part of an IC. In addition, the system 20 can be applied to a Human Interface Device (HID), such as a keyboard, a keyboard on a mobile phone, a joystick, and a remote controller.
The controller 22 is coupled to the quartz oscillator 13 and the transmitter 24. When the controller 22 receives a trigger to start the crystal oscillator 13 or transmit the modulated signal, the controller 22 may start the crystal oscillator 13 by using a start signal ACT1, so that the crystal oscillator 13 generates a reference signal REF, which is then transmitted to the transmitter 24 via the frequency selection pin 24-3. The controller 22 may be configured to determine whether the quartz oscillator 13 has stabilized by receiving a feedback signal (not shown) from the quartz oscillator 13 or having a counter (not shown) to count for a predetermined period of time. The time of the predetermined period is approximately the time required to stabilize the quartz oscillator 13, and the time can be determined by experiments. Once the controller 22 has determined that the crystal oscillator 13 has stabilized, the controller 22 may cause the phase-locked loop frequency synthesizer 24-1 to generate a carrier signal based on the reference signal REF and cause the transmitter to generate a modulated signal according to the method described below with reference to fig. 5. In addition, since the controller 22 is a digital circuit, it requires a pulse signal to operate. In one example, the controller 22 may include an internal oscillator (not shown) for generating the pulse signal. In addition, the controller 22 may receive the pulse signal from the external quartz oscillator 13. Furthermore, in another embodiment, the transmitter 24 may include another frequency selection pin (not shown) to receive a signal from the controller 22 and transmit the received signal to the PLL frequency synthesizer 24-1 to fine tune the frequency of the carrier signal generated by the PLL frequency synthesizer 24-1.
Fig. 5 is a timing diagram illustrating the signals generated by the crystal oscillator 13, phase-locked loop frequency synthesizer 24-1, power amplifier 24-2 and transmitter 24 of fig. 4 after the trigger is received by controller 22. First at time t1, the controller starts the quartz oscillator 13 to generate a reference signal REF, which is sent to the phase-locked loop frequency synthesizer 24-1 of the transmitter 24. Once the controller 22 determines that the crystal oscillator 13 has stabilized, the controller 22 may transmit a first modulated signal MOD1 generated by the modulator 22-1 to the PLL frequency synthesizer 24-1 via the modulation pin 24-4. Phase-locked loop frequency synthesizer 24-1 is enabled by first modulated signal MOD1 and generates a carrier signal based on the frequency of reference signal REF. The carrier signal is then passed to the power amplifier 24-2. As shown in fig. 5, the phase-locked loop frequency synthesizer 24-1 is started at time point t2 and is stabilized at time point t 3. The time required to stabilize phase-locked loop frequency synthesizer 24-1 is approximately 100 microseconds (mus). The time may vary depending on the design of the phase locked loop frequency synthesizer. The controller 22 may determine whether the phase-locked loop frequency synthesizer 24-1 has stabilized by receiving a feedback signal (not shown) from the phase-locked loop frequency synthesizer 24-1 or having a counter (not shown) to count a predetermined period of time (e.g., 100 mus) required for the phase-locked loop frequency synthesizer 24-1 to stabilize. Once controller 22 determines that phase-locked loop frequency synthesizer 24-1 has stabilized, power amplifier 24-2 is turned on and off in response to, for example, the rising and falling edges of a second modulated signal MOD2, respectively, to generate a modulated signal based on the carrier signal and second modulated signal MOD 2. Therefore, as illustrated in fig. 5, the power amplifier output may have the same waveform as the second modulation signal MOD 2.
In one example, the PLL frequency synthesizer 24-and the power amplifier 24-21 are driven off by the falling edge of the second modulation signal MOD 2. In another example, the phase-locked loop frequency synthesizer 24-1 may be turned off after the power amplifier 24-2 has been turned off. The first modulated signal MOD1 and the second modulated signal MOD2 may be two signals with the same frequency and amplitude but different phases. In an example consistent with the present invention, transmitter 24 may include a phase delay circuit (not shown) that receives a single modulation signal from controller 22 and generates first modulation signal MOD1 and second modulation signal MOD 2. For example, the phase delay circuit may include a buffer for causing a delay of the received modulated signal, thereby generating a second modulated signal MOD2, wherein the second modulated signal MOD2 has a different phase than the received modulated signal. In another example according to the present invention, two modulated signals MOD1 and MOD2 are generated by modulator 22-1 and sent to PLL synthesizer 24-1 and power amplifier 24-2 via different modulation pins 24-4.
Phase-locked loop frequency synthesizer 24-1 may include a Voltage-controlled oscillator ("VCO") and a frequency divider, which are the most power consuming components of phase-locked loop frequency synthesizer 24-1. Thus, the phase locked loop frequency synthesizer 24-1 may be turned off by turning the VCO off. Once the VCO is turned off, the frequency divider will also be turned off. In response to the first modulation signal from the controller 22, the VCO may generate a carrier signal for the power amplifier 24-2. The modulated signal is then converted to a radio frequency signal and transmitted via an antenna 15 coupled to the transmitter 24.
The pll frequency synthesizer 24-1 of the first embodiment of the present invention shown in fig. 4 is not continuously turned ON (ON) during the whole period of time when the modulated signal is being generated, so the wireless short-range transmission system 20 according to the first example of the present invention consumes very little power and is more energy efficient than the wireless short-range transmission system of the conventional wireless keyboard. Specifically, it may again be assumed that: the bit time for transmitting information at 1kbps is the same for logic high and logic low bits (i.e., duty cycle is 50%), the voltages for logic high and logic low bits are 2V and 0V, respectively, and the currents for operating the quartz oscillator 13, the PLL frequency synthesizer 24-1 and the power amplifier 24-2 are 500 μ A, 5mA and 5mA, respectively. In addition, the lock time of the pll frequency synthesizer is generally about 1/10 times the bit time. Therefore, since the lock time of the pll frequency synthesizer is short enough to be ignored with respect to the bit time length, the current consumed during the lock time of the pll frequency synthesizer can be ignored. In addition, when the signal to be transmitted by the transmitter 24 is logic low, the most energy consuming component PLL synthesizer 24-1 is turned off by the modulation signals MOD1/MOD2, and the power amplifier 24-2 is also turned off. Alternatively, the phase locked loop frequency synthesizer 24-1 is turned off after the power amplifier 24-2 has been turned off. Therefore, the average current for transmitting a "1" and a "0" bit is only 5500 μ A, which is 2500 μ A less than the current operated by the wireless short range transmission system in the conventional wireless keyboard 10. Therefore, the energy efficiency of the first example of the present invention is about 11000nJ/bit, which is 5000nJ/bit less than that of the wireless short distance transmission system in the conventional wireless keyboard 10. In addition, the present invention uses RF signals to transmit the modulated signals, which is more energy efficient than using IR signals to transmit the modulated signals, and the wireless keyboard according to the present invention does not require a direct line of sight to operate. Therefore, those skilled in the art will appreciate that the first example of the present invention requires less energy to transmit than the conventional short-range wireless transmission system.
Fig. 6 is a block diagram of a wireless short-range transmission system 30 according to a second embodiment of the present invention. The second embodiment shown in fig. 6 is similar to the first embodiment shown in fig. 4, except that the second embodiment includes a transmitter 34; the transmitter 34 includes a fast lock phase locked loop frequency synthesizer 34-1, which is different from the phase locked loop frequency synthesizer 24-1 of the first embodiment. The fast pll synthesizer 34-1 has a significantly shorter lock time than the pll frequency synthesizer 24-1 and may be a digital or an analog pll frequency synthesizer. The fast lock PLL frequency synthesizer 34-1 may be, for example, an integer N-type PLL integrated with additional components to reduce the lock time. For example, it has been proposed to add a digital Discriminator-assisted phase detector ("DAPD") to an integer N-type phase locked loop to accelerate the loop to steady state. Another example of a fast lock phase locked loop frequency synthesizer 34-1 may be a fractional N-type phase locked loop, which has a more complex structure than the integer N-type phase locked loop, but has a shorter lock time. When the lock-in time is short, the bit rate may increase, thereby increasing the energy efficiency of the wireless short-range transmission system 30 as described below and with reference to fig. 7. The method of operation of the second embodiment is the same or similar to the method of operation of the first embodiment.
Fig. 7 is a timing diagram illustrating the signals generated by the crystal oscillator 13, the fast lock phase locked loop frequency synthesizer 34-1, the power amplifier 24-2 and the transmitter 34 of fig. 6 after the trigger is received by the controller 22. As shown in fig. 7, the lock time for fast locking phase locked loop frequency synthesizer 34-1 is approximately 10 mus, which is 10 times shorter than the lock time for phase locked loop frequency synthesizer 24-1. Thus, the bit rate of the transmitter 34 of the second embodiment is 10kbps, which is 10 times higher than the bit rate of the transmitter 24 of the first embodiment. Thus, according to the second embodiment of the present invention, the average current for transmitting a "1" and a "0" bit is 5500 μ A, but since the bit rate is increased by 10 times due to the shorter lock-in time, the energy efficiency of the second embodiment of the present invention is about 1100nJ/bit, which is 10 times more than that of the first embodiment. In other words, the second embodiment of the present invention uses less energy to transmit information.
Fig. 8 is a block diagram of a wireless keyboard 40 according to a third embodiment of the present invention. The wireless keyboard 40 includes a wireless short-range transmission system similar to or identical to the wireless short-range transmission system according to the first and second embodiments shown in fig. 4 and 6. The wireless keyboard 40 further includes a key matrix 11 and a set of keys (not shown) connected to the key matrix 11. The controller 42 is configured to scan the key matrix 11 to find one or more signals therefrom that represent that "one or more keys are being pressed". If one or more signals representing "one or more keys are being pressed" are received by the controller 42, the controller 42 may cause the wireless short-range transmission system to generate and transmit modulated signals in a manner similar or identical to the wireless short-range transmission system according to the first and second embodiments.
The fourth embodiment of the present invention is a wireless keyboard having the same components as the wireless keyboard 40, except that the transmitter 44 of the fourth embodiment may be the same as or similar to one of the transmitter 14 shown in fig. 1, the transmitter 24 shown in fig. 4, or the transmitter 34 shown in fig. 6. The method of operation of the fourth embodiment is the same as or similar to the method of operation of the third embodiment except that the controller 42 of the fourth embodiment is configured to activate the quartz oscillator 13 and the transmitter 44 in response to a selection signal received from the key matrix 11. For example, the controller 42 of the fourth matrix case may be configured to determine that: determining whether the received one or more signals correspond to one or more of the first or second type of key, and determining therefrom: whether or not to activate the quartz oscillator 13 and the transmitter 44 to transmit information. Each of the first type of keys is associated with its own function. The first type of keys include, for example, text keys, function keys (F1, F2, etc.), lock keys, navigation keys (up, down, etc.), and edit keys (delete, enter, etc.), which are typically arranged in a QWERTY pattern. The second type of key is a modifier key that is only active when pressed simultaneously with other keys. Examples of the second type of key include Ctrl, Alt, and Shift.
If the received signals correspond to one of the first type of key, the controller 42 will trigger the quartz oscillator 13 and the transmitter 44 in the same or similar manner as the first and second embodiments. However, if the received signals correspond to only one of the second type of key, controller 42 will not transmit any signal to activate either quartz oscillator 13 or transmitter 44. In contrast, the controller 42 takes the form of a wait for a subsequent signal from the key matrix 11. When the controller 42 waits for a subsequent signal, the controller 42 may turn off its power supply completely, or turn off some of the components. In an alternative example of the fourth embodiment, the quartz oscillator 13 is first activated when a signal representing that a key has been pressed is received by the controller 42, and during subsequent operation the transmitter 44 is activated only when the received signal or signals are determined to correspond to one or more of the first or second type of key.
FIG. 9 is a process flow diagram showing: after the digital controller 42 receives one or more signals from the key matrix 11 indicating that one or more keys are being pressed, the controller 42 may execute and determine whether a signal must be sent to activate the transmitter 44. In step 111, the controller 42 scans the key matrix 11. In step 112, the controller 42 determines whether two or more keys are being pressed. If two or more keys are being pressed, the controller 42 proceeds to step 113 to determine whether there is a key code corresponding to a combination of the two or more pressed keys. For example, the combination of "Shift" and "a" corresponds to the key code "a", whereas the combination of "Alt" and "Shift" may not correspond to any key code. The controller 42 proceeds to activate the quartz oscillator 13 and the transmitter 44 if there is a key code corresponding to a combination of the two or more pressed keys, or activates only the transmitter 44 when the quartz oscillator 13 has been activated, and transmits data via the transmitter 44 in step 115. The controller 42 may activate the quartz oscillator 13 and the transmitter 44 and transmit the key code corresponding to the combination of the two or more pressed keys via the transmitter 44 according to any one of the methods described above with respect to the first and second examples shown in fig. 4 to 7. On the other hand, if the controller 42 determines in step 113 that there is no key code corresponding to the combination of the two or more pressed keys, the controller 42 does not activate the transmitter 44.
If, in step 112, the controller 42 determines that only one key is being pressed, the controller 42 proceeds to step 114 to determine whether the pressed key is one of the first or second type of key. If the pressed key is the first type of key, controller 42 may proceed to step 115. Otherwise, if the pressed key is a second type of key, controller 42 does not activate transport 44. Finally, the controller 42 may remain idle or turn off its power supply until another signal is received from the key matrix 11.
Fig. 10 is a timing diagram of signals that illustrate the timing of the signals received by the controller 42 from the key matrix 11 and the signals transmitted by the transmitter 44. As shown in fig. 10, when a "Shift" key, which is one of the second type of keys, is pressed, no data is being transmitted through the transmitter 44. Then, when the "Shift" key and the "a" key are simultaneously pressed and it is determined that the combination of the two keys corresponds to "a", the transmitter 44 sends out the key code of "a". In one example, when the controller 42 receives a signal indicating that "one or more keys are being pressed", the controller 42 may send a first enable signal ACT1 to the quartz oscillator 13, thereby causing the quartz oscillator 13 to generate a reference signal REF. Controller 42 may then scan key matrix 11 to determine which keys are being pressed. For example, if the key signal "Shift" and the key signal "a" from the key matrix 11 are received by the controller 42 at the same time, after the crystal oscillator 13 has stabilized, the controller 42 transmits a modulation signal representing the key code "a" to the transmitter 44.
The circuitry of the wireless keyboard 40 generally includes a Printed circuit board ("PCB") and an IC chip. The manufacture of the wireless keyboard 40 generally comprises the steps of: manufacturing ICs on a wafer in a wafer fab; testing the wafer; packaging the IC; and soldering the IC to a PCB board. The PCB board is generally designed according to an application of the PCB board. Fig. 11 illustrates a process for manufacturing a wireless keyboard 40 according to an example of the present invention. When an IC is being designed, a first number of pins is designated as associated with a first type of key and a second number of pins is designated as associated with a second type of key. The IC is then fabricated in a fab according to the design concept of the IC. Based on pin designations from the fab, customers can design a low power keyboard or keypad with keys at desired locations on a Printed Circuit Board (PCB). The customer's PCB can then be manufactured accordingly. Thus, the controller 42 in a wireless keyboard 40 constructed according to the method described above will be able to determine whether the signals received from the key matrix 11 represent a first type of key or a second type of key and determine whether to transmit signals via the transmitter 44 according to the method described above in connection with FIG. 9.
The wireless keyboard 40 according to the present invention is operable in at least one of two modes: an active mode when the user is transmitting information using the wireless keyboard 40; and a standby mode when the user is not using the wireless keyboard 40. When the wireless keyboard 40 is operating in the start mode, the controller 42 repeatedly executes the method described in fig. 9 until a predetermined period of time has elapsed during which the controller 42 does not receive any signals from the key matrix 11. After the predetermined period of time has elapsed, the wireless keyboard 40 switches to the standby mode. When the wireless keyboard 40 is in the standby mode, power to all of the components in the wireless keyboard may be turned off. When it is in the standby mode, the controller 42 receives a signal from the key matrix 11, and the controller 42 switches to the start-up mode and starts the routine described in fig. 9.
Fig. 12 is a block diagram of a wireless keyboard 50 according to a fifth embodiment of the present invention. The wireless keyboard 50 is similar to the wireless keyboard 40 according to the fourth embodiment of the present invention, with the difference that: the wireless keyboard 50 further includes a memory 46 in which information is pre-stored regarding the mapping of the keys to their addresses relative to the memory, and information indicating whether each key is of the first type or of the second type. The controller 52 is configured to determine whether the one or more signals received correspond to one or more of the first type of key or the second type of key based on the one or more signals received from the key matrix 11 and information previously stored in the memory 46.
Fig. 13 is a diagram illustrating an example of the memory 46 and the relationship between information stored in the memory 46 and the keys on the keyboard 50. Each key on the keyboard 50 is mapped to an address in the memory 46. The content of each address represents whether the key corresponding to the address is one of the first type key or the second type key. For example, "0" may represent a first type of bond, and "1" may represent a second type of bond.
Fig. 14 illustrates a process for manufacturing a wireless keyboard 50 according to an example of the present invention. In the design stage, the position of each key on the PCB is determined by the customer or application, and the PCB is manufactured according to the determined position. Since the routing is performed for each key according to the kind of each key at the stage of designing the PCB board, it becomes complicated and limited due to the complicated structure of the routing and the routing; thus, all keys are designed to be able to transmit signals when the IC is being designed. And, the IC is manufactured in a wafer fab according to the concept of IC design. Information regarding the location and type of each key may be recorded in memory 46 during wafer testing, IC packaging, or after the IC is soldered to the PCB board. By manufacturing the wireless keyboard according to the above-described procedure, the keyboard can be customized according to the application and the needs of the customer. For example, the wiring for the keyboard of a palmtop device may be different from the wiring for a desktop or laptop computer. Thus, the location of the keys may be different on each keyboard. By the above-described procedure, the IC can enable all the equal keys to transmit signals through a special design. The non-transmitting nature of the second type of keys may be achieved by recording information in the memory during wafer testing, IC packaging, or after the IC is soldered to the PCB board once the customer or application mode of the keyboard has been determined. Therefore, it is possible to provide wireless keyboards having different sizes with energy efficiency.
In describing representative examples of the present invention, the specification has presented the method and/or process of operating the invention as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other sequences of steps are possible, as will be appreciated by those skilled in the art. Accordingly, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. Moreover, the claims directed to the method and/or process of the present invention should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the present invention.
Claims (10)
1. A wireless keyboard, comprising:
a plurality of keys, wherein said plurality of keys comprises a set of keys of a first type and a set of keys of a second type, each of said plurality of keys of the first type being associated with one of a plurality of predetermined functions;
a transmitter, the transmitter comprising a phase-locked loop frequency synthesizer and a power amplifier;
an antenna; and
a controller coupled to the plurality of keys and the transmitter, wherein the controller is configured to:
receiving a first signal from the plurality of keys, the first signal indicating that at least one of the plurality of keys has been selected,
determining whether a selected at least one of the plurality of keys is one of the plurality of first keys based on the first signal,
activating the transmitter to transmit a second signal via the antenna if the selected at least one of the plurality of keys is one of the first plurality of keys, wherein the second signal carries information for one of the predetermined plurality of functions associated with the selected at least one of the plurality of keys;
determining whether the selected at least one of the plurality of keys is one of the plurality of keys of the second type based on the first signal, and
if one of the plurality of keys is selected and is one of the plurality of second keys, the controller turns off the power amplifier to cause the power amplifier to stop transmitting signals, or the controller turns off the phase-locked loop frequency synthesizer to cause the phase-locked loop frequency synthesizer to stop transmitting signals.
2. The wireless keyboard of claim 1, wherein the controller is further configured to:
determining whether the selected at least one of the plurality of keys comprises two or more keys, an
If the selected at least one of the plurality of keys comprises two or more keys, the controller is further configured to determine whether a combination of the two or more keys corresponds to one of the plurality of predetermined functions, and if the combination of the two or more keys corresponds to one of the plurality of predetermined functions, activate the transmitter to transmit a third signal via the antenna, wherein the third signal carries information of the one of the plurality of predetermined functions associated with the combination of the two or more keys.
3. The wireless keyboard of claim 2, wherein each of the plurality of second type keys is associated with one of the plurality of predetermined functions only when each of the plurality of second type keys and at least another one of the plurality of keys is received by the controller.
4. The wireless keyboard of claim 3,
the first set of keys includes at least one of letter, number, symbol, punctuation keys, enter, backspace, skip and caps lock keys, and the second set of keys includes at least one of control, shift and convert keys.
5. The wireless keyboard of claim 1, further comprising:
a memory coupled to the controller, wherein the memory is configured to store predetermined information indicating each of the plurality of keys as one of the plurality of first keys or one of the plurality of second keys, and wherein
The memory includes a plurality of memory locations, each memory location identified by a memory address, the memory configured to store predetermined mapping information associated with the plurality of keys and the plurality of memory locations, each of the plurality of memory locations storing a flag indicating a corresponding one of the plurality of keys as the first key or the second key, and
the controller determines whether the selected at least one of the plurality of keys is one of the plurality of first type keys based on the predetermined information.
6. The wireless keyboard of claim 1, further comprising:
a first oscillator; and
wherein,
the phase-locked loop frequency synthesizer is configured to receive a reference signal from the first oscillator and a first modulation signal from the controller, wherein the phase-locked loop frequency synthesizer is configured to be turned on by the first modulation signal to generate a carrier signal based on the reference signal; and
the power amplifier is configured to receive the carrier signal and a second modulation signal from the phase-locked loop frequency synthesizer, wherein the power amplifier is configured to be turned on and off by the second modulation signal to thereby generate the second signal based on the carrier signal, wherein the power amplifier is turned on after the phase-locked loop frequency synthesizer is stabilized, and the phase-locked loop frequency synthesizer is turned off as the power amplifier is turned off, or after the power amplifier has been turned off.
7. The wireless keyboard of claim 6, wherein the transmitter further comprises a frequency selection pin and at least one modulation pin;
the phase-locked loop frequency synthesizer receives the reference frequency signal from the first oscillator through the frequency selection pin and receives the first modulation signal from the controller through the at least one modulation pin;
the power amplifier receives the second modulation signal from the controller through the at least one modulation pin; and
the controller includes one of an amplitude keying and an on-off keying modulator for generating the first modulated signal and the second modulated signal, wherein the first modulated signal and the second modulated signal have the same frequency and amplitude but different phases.
8. The wireless keyboard of claim 7, wherein the controller is configured to:
transmitting a third signal to the first oscillator to start the first oscillator;
transmitting the first modulation signal to the at least one modulation pin to activate the phase-locked loop frequency synthesizer at one of:
(i) when the controller receives a first feedback signal from the first oscillator representing an indication that the first oscillator has stabilized, an
(ii) After a first predetermined period of time, the first predetermined period of time is the time to stabilize the first oscillator; and
transmitting the second modulated signal to the power amplifier at one of:
(i) when the controller receives a second feedback signal from the PLL frequency synthesizer indicating that the PLL has stabilized, an
(ii) After a second predetermined period of time, the second predetermined period of time is the time to stabilize the phase-locked loop frequency synthesizer.
9. The wireless keyboard of claim 7, further comprising a key array, wherein
The controller is configured to receive the first signal indicating that at least one key of the wireless keyboard is being pressed from the plurality of keys via the key array.
10. The wireless keyboard of claim 6,
the controller comprises one of a microprocessor and a microcontroller;
the PLL frequency synthesizer comprises one of a digital PLL frequency synthesizer, an analog PLL frequency synthesizer, a digital fast PLL and an analog fast PLL, wherein the PLL frequency synthesizer further comprises a second oscillator and is turned on or off by turning on or off the second oscillator; and
the modulated signal is converted into a radio frequency signal and transmitted.
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TW100108123A TWI520167B (en) | 2011-03-10 | 2011-03-10 | Low power wireless keyboard |
TW100108123 | 2011-03-10 |
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CN102681668A CN102681668A (en) | 2012-09-19 |
CN102681668B true CN102681668B (en) | 2015-06-17 |
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TWI547832B (en) * | 2015-07-06 | 2016-09-01 | Dexin Corp | An input device with adaptive adjustment and its adjustment method |
WO2017183888A2 (en) | 2016-04-19 | 2017-10-26 | Samsung Electronics Co., Ltd. | Positioning method and apparatus |
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CN1125334A (en) * | 1994-12-19 | 1996-06-26 | 巨太国际股份有限公司 | Wireless keyboard system of computer |
CN1185603A (en) * | 1996-12-18 | 1998-06-24 | 王林 | Method for inputting Chinese punctuation and mark by keyboard |
US5854621A (en) * | 1991-03-19 | 1998-12-29 | Logitech, Inc. | Wireless mouse |
US7151915B2 (en) * | 2001-09-26 | 2006-12-19 | Nokia Corporation | Dual mode voltage controlled oscillator having controllable bias modes and power consumption |
Family Cites Families (2)
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US20070253468A1 (en) * | 2006-05-01 | 2007-11-01 | Micrel Inc. | Spread Spectrum ASK/OOK Transmitter |
US20080195762A1 (en) * | 2007-02-13 | 2008-08-14 | Wood Michael C | Multifunction data entry device and method |
-
2011
- 2011-03-10 TW TW100108123A patent/TWI520167B/en active
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2012
- 2012-02-10 CN CN201210030380.4A patent/CN102681668B/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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US5854621A (en) * | 1991-03-19 | 1998-12-29 | Logitech, Inc. | Wireless mouse |
CN1125334A (en) * | 1994-12-19 | 1996-06-26 | 巨太国际股份有限公司 | Wireless keyboard system of computer |
CN1185603A (en) * | 1996-12-18 | 1998-06-24 | 王林 | Method for inputting Chinese punctuation and mark by keyboard |
US7151915B2 (en) * | 2001-09-26 | 2006-12-19 | Nokia Corporation | Dual mode voltage controlled oscillator having controllable bias modes and power consumption |
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TW201237905A (en) | 2012-09-16 |
CN102681668A (en) | 2012-09-19 |
TWI520167B (en) | 2016-02-01 |
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