摘要:
An active matrix device includes a data line driver circuit for sampling the input signal to produce data signals for each of the rows of control elements in a corresponding line period, and a scan line driver circuit for addressing the scan lines sequentially by applying a scan signal to the scan inputs of the control elements along each of the rows so as to supply said data signals to the control elements along the row. Such circuits are controlled so that a data input signal is sampled and stored to produce data signals for a first group of the control elements along the row in a first line subperiod and the stored data signals are applied to the first group of control elements in a second line subperiod, and so that the data input signal is sampled and stored to produce data signals for a second group of control elements along the row in the second line subperiod and the stored data signals are applied to the second group of control elements in a subsequent line subperiod.
摘要:
A fault tolerant circuit arrangement includes: an input; an output; a first circuit element, a second circuit element, a third circuit element, and a fourth circuit element, provided in such a manner that the first and second circuit elements are connected in series between the input and the output to form a first series combination, and the third and fourth circuit elements are connected in series between the input and the output to form a second series combination, the first series combination being connected in parallel with the second series combination between the input and the output; and, a control element connected between an interconnection point of the first and second circuit elements and an interconnection point of the third and fourth circuit elements. The control element is switchable by a control signal between a conducting mode in which current flow is enabled between the interconnection points and a non-conducting mode in which current flow is prevented between the interconnection points.
摘要:
A fault tolerant circuit arrangement comprises a plurality of replicated non-redundant shift registers 30 connected in parallel and each having an enable/configuration input 31 and a plurality of outputs 36. Furthermore each register 30 includes a verify output 32 for outputting a verify signal indicating whether or not a fault condition is present within the register. The arrangement also includes a verification signal generator 33 for applying a fixed reference signal, a comparator 34 to which the verify signals from the outputs 32 are applied, and a control circuit 35. The test/control-logic of the comparator 34 and control circuit 35 is constructed using masking redundancy 20-24 in order to render the test/control logic tolerant to faults. The control circuit 35 serves to control testing of each of the registers 30 in turn by supplying an enable signal to the input 31 of each register 30 beginning with the first register. This causes the supply of a verify signal V.sub.1 from the verify output 32 of the first register 30 to the comparator 34 which compares the verify signal V.sub.1 to the reference signal. If the verify signal V.sub.1 is significantly different from the reference signal, this indicates that there is a fault present in the first register, and the control circuit 35 is caused to supply a disable signal to the input 31 of the first register. The test procedure is repeated for each register 30 until a verify signal is received by the comparator 34 which indicates that there is no fault present in the associated register.
摘要:
A data line driver is provided for driving M data lines of a matrix display such as a liquid crystal display. The driver comprises x data line circuits whose inputs are connected to a common input for receiving a serial image signal, where x is less than M. Each of the data line circuits comprises a store for storing one picture element of image data at a time, a multiplexer for storing in the store in sequence image data for m picture elements from at least part of a line of image data, where m is greater than one, and a demultiplexer for directing a line signal corresponding to the image data stored in the store to each of m of the M data lines in sequence.
摘要:
A data line driver circuit for an active matrix liquid crystal display comprises a distributed controller in the form of a control shift register comprising a chain of control DFF's and associated detection logic. Furthermore the drive circuit includes a respective driver stage under the control of each control DFF for sampling the n-bit digital input signal and for supplying a drive signal to a corresponding data line. Each of the driver stages incorporates an n-bit vertically connected sample shift register composed of DFF's and associated 2:1 multiplexers which are used to provide an input either from the relevant bit line of the n-bit input data bus or from the output of the preceding DFF. In operation the n-bits of the input signal are supplied in parallel to the n inputs of the DFF's in a sampling mode, and the n-bits are shifted along the sample shift register towards the output of the shift register in a shifting mode. A serial D/A converter receives the n-bits sequentially and produces an analogue drive signal for driving the data line.
摘要:
In one embodiment of the present invention, a drive circuit includes: a logic block connected between a source of a first voltage and a source of a second voltage, and a sampler including a plurality of sampling circuits. Each sampling circuit is for sampling, in use, an input data signal and outputting a voltage to a respective output. The drive circuit further includes a voltage booster having plurality of voltage boost circuits, each voltage boost circuit being associated with a respective one of the sampling circuits and, in use, generating a boosted voltage signal and providing the boosted voltage signal to the respective sampling circuit. Each voltage boost circuit is connected between the source of the first voltage and the source of the second voltage. The logic block may be, but is not limited to, a shift register.
摘要:
A signal line driving circuit includes a shift register having a plurality of shift circuits, each of which shifts a start pulse successively to the next stage, synchronizing with the timing of a clock signal. In this signal line driving circuit, shift pulses are outputted from an AND gate based on output pulses of two adjacent shift circuits. Meanwhile, a width specifying pulse for specifying a pulse width of the shift pulse is inputted via a transistor whose ON/OFF operation is controlled by the shift pulse. A logical operation circuit operates an AND of the shift pulse and the width specifying pulse and outputs the result of operation to a signal line. When the shift pulse is non-active, the transistor becomes OFF, which causes the signal line transmitting the width specifying pulse to be disconnected from the signal line driving circuit, thereby reducing a capacitive load of wiring. As a result, reduction of a parasitic capacitance of the wiring, reduction in the number of elements, reduction in the size of an amplitude of an input signal, etc. in the signal line driving circuit are attained.
摘要:
A frame rate controller (20) is provided for controlling the frame refresh rate of an active matrix display. The controller (20) comprises a first circuit such as a preloadable synchronous counter (21) which counts vertical synchronization signals VSYNC and supplies an enable signal FE for every Nth frame of data, where N is an integer greater than zero and is selectable. A gating arrangement (26) is controlled by the enable signal FE so that an active matrix display is refreshed for every Nth frame of data, thus allowing a reduction in power consumption of the display.
摘要:
Multi-format sampling registers, digital to analogue converters, data drivers and active matrix displays are provided which provide power saving in lower resolution formats by disabling circuitry which is not required in those formats.
摘要:
A level-shifting pass gate comprises a field effect transistor (M1) whose source is connected to a signal input (IN) and whose drain is connected to a signal output (OUT). A load (R) is connected between the drain of the transistor (M1) and a supply line (vdd). A control means (1) has an enable input (EN) which receives signals for enabling or disabling the pass gate. When the gate is enabled, the control means (1) controls the transistor (M1) and possibly the load (R) so that an input logic low level is passed substantially unchanged whereas a relatively low input high level is shifted to a higher output logic high level approaching the supply voltage. When the pass gate is disabled, the transistor (M1) is switched off so that the input (IN) is isolated from the output (OUT) and assumes a high impedance state. Conversely, when disabled, the output (OUT) defaults to a predetermined state, such as logic low, logic high or high impedance.