Abstract: Compensation needed to be made for reduced light efficiency in aged sub-pixels of an active matrix organic light-emitting diode (OLED) display are determined using a current ratio or a voltage ratio pertaining to an aged sub-pixel relative to un-aged, reference sub-pixels. When the current through the sub-pixels or the voltage across the sub-pixels are measured to determine the age of the sub-pixels, correction is made to the measured current or voltage to account for variations in the ambient temperature in which the OLED display is placed.

Abstract: The data line voltage on the data line of the AMOLED sub-pixels is measured while the OLED is being driven by a reference current, in order to determine the age of the OLED in the sub-pixel. The pixel transistor serves as a current source for driving the OLED in the sub-pixel with the reference current. The data line voltage is substantially equal to the forward voltage VF(aged) of the aged OLED being driven at the reference current. The forward voltage VF (un-aged) of a reference (un-aged) OLED sub-pixel also measured at the reference current, and is subtracted from the measured OLED diode forward voltage VF (aged) to obtain their difference ?VF=VF(aged)?VF(un-aged). ?VF is an indicator of the age of the OLED in the sub-pixel, and is used as an index to a look-up-table that stores the corresponding aging offset data for generating the incremental pixel current needed to maintain constant luminance in the aged OLED pixel.

Abstract: The scanned channel and the non-scanned channels of a capacitive touch sensor are driven by a scan signal and a shield signal, respectively, with the shield signal having a substantially same amplitude and a substantially same phase as the amplitude and the phase, respectively, of the scan signal. Thus, the potentials at both the routing line of the scanned channel and the routing line of the non-scanned channels follow each other and are maintained substantially same regardless of which channel is the scanned one. As a result, the parasitic capacitance arising between the two routing lines is reduced significantly, and the accuracy and the sensitivity of the touch sensor are significantly enhanced.

Abstract: A touch screen includes a plurality of single-layer ITO bars having a substantially rectangular shape and arranged in parallel to each other in order to detect touches on the touch screen. The location of a touch on the touch screen in the direction along an ITO bar is determined by applying a signal on one end of the ITO bar and measuring the change in the amplitude and the delay of the signal on the opposite end of the ITO bar. Such application and measurement of the signal can be repeated with the application of the signal occurring on the opposite end of the ITO bar and the measurement of the signal occurring on said one end of the ITO bar, in order to enhance the accuracy of the measurement.

Abstract: A key is determined to be the user-selected key of a touch sensitive input device if the touch on the key is determined to be valid continuously for longer than a first predetermined period of time. Another key may be determined to the user-selected key, replacing the previously determined user-selected key, if the touch on another key is valid continuously for a second predetermined period of time that may be longer than the first predetermined period of time.

Abstract: Sub-pixel current in an OLED display is forced to converge to a desired level regardless of the source of pixel current error. By using a feedback loop, the pixel transistor current is forced to be equal to a predetermined target current that is established by an analog control circuit. The predetermined target current is selected to generate the desired pixel transistor current through the sub-pixel, and can be set by setting a target voltage. The sub-pixels have a 3T cell structure including 3 TFTs, one TFT for connecting the data line to the storage capacitor, another TFT for driving the sub-pixel current, and still another TFT for connecting the OLED diode anode to the data line of the AMOLED panel.

Abstract: A plurality of gray level versus OLED current curves are generated by measuring many OLED panels from a stable manufacturing process, and those curves are stored as standard gray level versus OLED current curves. When a new OLED display is manufactured from the process, each of its sub-pixels is characterized as having the characteristics of one of the pre-generated standard gray level versus OLED current curves, based on a gray level versus OLED current measurement at a single gray level. This drastically reduces the time it takes to determine the TFT gate voltage versus OLED current characteristics of the sub-pixels in the OLED display. The OLED display can use the selected one of the pre-generated standard gray level versus OLED current curves to correct non-uniformities of the sub-pixels in the OLED display caused by non-uniform TFTs in the active matrix.

Abstract: A combined touch sensor and light-emitting-diode (LED) driver comprises a touch sensor circuit configured to detect a touch, where the touch sensor circuit is coupled to a common node and configured to operate with a first operating voltage, an LED driver circuit configured to drive an LED if the LED is coupled to the common node, where the LED driver circuit is also coupled to the common node and configured to operate with a second operating voltage is higher than the first operating voltage, and an n-type field effect transistor (FET) connected in series between the common node and the touch sensor. The n-type FET prevents the higher operating voltage of the LED driver from affecting the operation of the touch sensor, when a port of the combined touch sensor and LED driver IC is used to drive an LED. The touch sensor may be a capacitance-to-digital converter.

Abstract: An LED driver includes an embedded non-volatile memory (NVM) capable of being programmed and storing control data for setting a variety of features of the LED driver, such as the maximum current for driving the LEDs, analog parameters such as the resistance of the internal resistor for setting the reference current for the LEDs, and the operation modes of the charge pump of the LED driver. This enables implementation of multiple LED driver product options without the need for different metallization steps during the fabrication process for the LED driver.

Abstract: Provided are a device for driving a touch pad, including: an input unit that receives an electrical signal be touching from channels of the touch pad; and a control logic unit that scans the channels. The control logic unit includes a channel selection section which divides the touch pad into a plurality of regions and selects the channels which are to be scanned, wherein the ration of the number of total channels to the number of channels to be scanned is different according to each of the plurality of divided regions. In accordance with the present invention, the scanning speed of the touch pad is improved and, thereby, the response speed of other elements which are operated depending on whether the touch pad is touched or not is enhanced.

Abstract: A new Class L amplifier which dynamically switches between multiple pairs of power rails, and has the ability to select the most advantageous combination of rails for the minimization of power dissipation in the amplifier. A bridged amplifier system using two Class L amplifiers to drive a load.

Abstract: A new Class L amplifier which dynamically switches between multiple pairs of power rails, and has the ability to select the most advantageous combination of rails for the minimization of power dissipation in the amplifier. In one embodiment, a bridged amplifier system includes two Class L amplifiers to drive a load.

Abstract: Disclosed are a device and a method for driving a display element that adjusts a backlight luminescence to be suitable for a mean luminescence of an image data for each frame, analyzes the mean, maximum and minimum luminescence of an image to be displayed to reduce power consumption due to unnecessary backlight luminescence, and then adjusts the backlight luminescence in accordance with the analyzed result. The device for driving a display element includes a buffer memory, a histogram analyzer, a main memory, a maximum luminescence determining and mapping unit and a digital-to-analog converter (DAC). When an image data to be displayed for each frame is inputted to the buffer memory, the histogram analyzer analyzes the image data for each frame to calculate a mean luminescence, a maximum/minimum luminescence and a histogram for each of the R, G and B colors, and then outputs the analyzed image data for each frame to the maximum luminescence determining and mapping unit.

Abstract: An active matrix drive system drives an emissive display device such as an organic light-emitting diode display and is configured to measure sub-pixel current in the emissive display device. One or more power column power lines of the emissive display device are turned off while sub-pixel current is measured. As a result, the sub-pixel current is relative large compared to the background current of the emissive display device, which facilitates accurate measurement of the sub-pixel current.

Abstract: An improved Class G type amplifier is provided which switches between multiple power rails depending upon the instantaneous amplitude of the input signal versus the power rails without excessive distortion. The low voltage (inner) amplifier includes a plurality of parallel amplifier devices, and the high voltage (outer) amplifier includes a plurality of parallel amplifier devices. A plurality of switches each couples the input signal to either a respective one of the inner amplifier devices or a respective one of the outer amplifier devices. The switches are activated sequentially, such that the switching from inner amplifier devices to outer amplifier devices or vice versa is staggered over time. This avoids having a single, large glitch in the output and spreads multiple smaller glitches over enough time so that some of the radiated glitch energy can fall within frequencies where amplifier feedback circuitry can eliminate its noise. The switches are sequentially activated by a series of delay elements.

Abstract: Compensation needed to be made for reduced light efficiency in aged sub-pixels of an active matrix organic light-emitting diode (OLED) display are determined using a current ratio or a voltage ratio pertaining to an aged sub-pixel relative to un-aged, reference sub-pixels. When the current through the sub-pixels or the voltage across the sub-pixels are measured to determine the age of the sub-pixels, correction is made to the measured current or voltage to account for variations in the ambient temperature in which the OLED display is placed.

Abstract: The current drivers of an emissive display device such as an OLED display are shut off to have minimum drain current when sub-pixel current is measured, in order to minimize dark current during sub-pixel current measurement. The current drivers in the sub-pixels not under test are biased in such a manner as to reduce their leakage current to a minimum. Therfore, the signal to noise ratio between the OLED sub-pixel current and the panel dark current can be maximized.

Abstract: Compensation needed to be made for reduced light efficiency in aged sub-pixels of an active matrix organic light-emitting diode (OLED) display are determined using a current ratio or a voltage ratio pertaining to an aged sub-pixel relative to un-aged, reference sub-pixels.

Abstract: An improved Class G type amplifier which switches between multiple power rails depending upon the instantaneous amplitude of the input signal versus the power rails. The low voltage (inner) amplifier includes a plurality of parallel amplifier devices, and the high voltage (outer) amplifier includes a plurality of parallel amplifier devices. A plurality of switches each couples the input signal to either a respective one of the inner amplifier devices or a respective one of the outer amplifier devices. The switches are activated sequentially, such that the switching from inner to outer amplifier devices or vice versa is staggered over some period of time. This avoids having a single, large glitch in the output, and spreads multiple smaller glitches over enough time that some of the glitch energy can fall within the frequency range where the amplifier's feedback circuitry can eliminate its noise. The switches are sequentially activated by a series of delay elements.

Abstract: A voltage reference generation circuit having switch pairs coupled to systematically commutate a flying capacitor among adjacent pairs of voltage rail outputs. The circuit requires only a single flying capacitor, N+1 switch pairs, and N storage capacitors, to generate N intermediate voltage references between VDD and GND. A signal generator produces N+1 non-overlapping switch enable signals to systematically enable the switch pairs and commutate the single flying capacitor between the rail pairs. The flying capacitor remains charged to VDD/(N+1). The N storage capacitors hold their respective reference outputs at VDD*N/(N+1), VDD*(N?1)/(N+1), VDD*(N?2)/(N+1), and so forth.