Nxp B.v.

Philips Lumileds Lighting Company LLC

Koninklijke Philips Corporation N.v.

Martijn H R Lankhorst

Franciscus Petrus Widdershoven

Teunis Willem Tukker

Aldegonda Lucia Weijers

Wouter Oepts

Hendrik G A Huizing

Pieter Grootes

Robert Hendriks

Christoph G A Hoelen

Lingli Wang

René J Hendriks

A module comprises a bus invert encoder () for determining whether a set of data bits should be inverted prior to transmission over a communication bus. The bus invert encoder () produces a bus invert signal BI which controls a selective inversion means (), for example a multiplexer. A partial fault detection encoder () determines one or more temporary check bits from the set of data bits, substantially in parallel with the bus invert encoder (). Thus, the one or more temporary check bits are determined based on the assumption that the set of data bits are to be transmitted without inversion from the selective inversion means (). A logic unit () is provided for correcting the one or more temporary check bits, if necessary, based on the bus invert signal produced by the bus invert encoder (). The module has the e advantage of enabling the temporary check bits to be determined in parallel with the bus invert encoding, thereby reducing latency, with the logic unit being used to correct the check bits, if necessary, prior to transmission over the communication bus.

Integrated circuit with memory cells comprising a programmable resistor and method for addressing memory cells comprising a programmable resistor

The present invention relates to an integrated circuit comprising a plurality of bitlines (b) and a plurality of word-lines (w) as well as a plurality of memory-cells (MC) coupled between a separate bit-line/word-line pair of the plurality of bit-lines (b) and wordlines (w) for storing data in the memory cell. Each memory cell (MC) comprises a selecting unit (T) and a programmable resistance (R). The value of the phase-change resistance (R) is greater than the value of a first phase-change resistance (R) defined by a supply voltage (V) divided by a maximum drive current (I) through said first phase-change resistor (R).

Integrated circuit with phase-change memory cells and method for addressing phase-change memory cells

An LED light source for LCD backlighting is described that recalibrates itself over time so that color and brightness uniformity across the backlight is maintained over the life of the backlight. The backlight contains clusters of red, green, and blue LEDs, each cluster generating a white point. In one embodiment, each color in a cluster has its own controllable driver so that the brightness of each color is a cluster is separately controllable. One or more optical sensors are arranged in the backlight, and the sensor signals are detected by processing circuitry to sense the light output of any LEDs that are energized in a single cluster. The measured white point and flux are compared to a stored target white point value and flux for that cluster. The currents to the RGB LEDs are then automatically adjusted to achieve the target level for each cluster. This process is applied to each cluster in sequence until the recalibration is complete. The recalibration takes place at various times over the lifetime of the backlight to offset the effects of LED degradation over time. Variations of this technique are also described.

LED backlight for LCD with color uniformity recalibration over lifetime

Various techniques are described for improving the color uniformity across a backlight for backlighting an LCD. In one embodiment, the backlight uses rows of red, green, and blue LEDs in a mixing chamber. The LEDs are arranged in clusters, such as GRBG or GBRG, each cluster having an associated white point. In order to achieve color uniformity along the left and right edges of the backlight, the LEDs in those edge clusters are specially selected to compensate for the color imbalance in the white point relative to the dimensions of the cluster. For example, a non-compensated cluster of GRBG along the left edge will produce a reddish tint along the left edge since the red peak intensity is to the left of the center of the cluster. To offset this reddish tint along the left side, the cluster's overall white point is blue-cyan shifted. As a result, the left edge of the backlight has the same white point as near the middle of the backlight, where the white point imbalance of a single cluster is offset by the white point imbalance of the surrounding clusters. Similarly, a GBRG cluster along the left edge will have its white point red-yellow shifted.

Multi-colored LED backlight with color-compensated clusters near edge

Growing community of inventors

Eindhoven, Netherlands

Martijn H R Lankhorst