Column Bus Driving Method For Micro Display Device

Abstract

A method of generating column signals for use by a pixel array includes connecting two or more controllable bus buffers in series. The output of each of the two or more controllable bus buffers drives an associated node. The method further includes providing a column data signal to an input of the series-connected string of two or more controllable bus buffers. The method also includes sequentially enabling each controllable bus buffer in the series-connected string of two or more controllable bus buffers, such that each node is sequentially driven. Each node is electrically coupled to an input of an associated controllable local output buffer. The method further includes sequentially enabling each of the controllable local output buffers in an order associated with the sequentially enabling of the controllable bus buffers.

What is claimed is: 
     
         1 . A microdisplay device comprising:
 a pixel array;   a column driver associated with the pixel array, comprising:
 two or more controllable bus buffers connected in series to form a series-connected string of two or more controllable bus buffers, each having an output driving an associated node; 
 two or more controllable local output buffers, each having an input electrically coupled to one of the associated nodes and having an output driving one or more columns of the pixel array; and 
 an enable controller driving one or more bus enable inputs of the series-connected string of two or more controllable bus buffers, and driving one or more local output enable inputs of the two or more controllable local output buffers; 
 wherein the enable controller sequentially enables each controllable bus buffer in the series-connected string of two or more controllable bus buffers, such that each node is driven according to a bus sequence. 
   
     
     
         2 . The column driver of  claim 1 , wherein the enable controller is configured to maintain each controllable bus buffer as enabled when a next subsequent controllable bus buffer is enabled. 
     
     
         3 . The column driver of  claim 1 , wherein the enable controller is a state machine. 
     
     
         4 . The column driver of  claim 1 , wherein the enable controller is a code-driven processor. 
     
     
         5 . The column driver of  claim 1 , wherein each controllable local output buffer, when not enabled, outputs a high-impedance state. 
     
     
         6 . The column driver of  claim 1 , wherein each controllable local output buffer, when not enabled, outputs a fixed logic state. 
     
     
         7 . The column driver of  claim 1 , wherein the one or more columns of the pixel array includes one or more DACs, such that the controllable local output buffer drives at least one DAC. 
     
     
         8 . The column driver of  claim 1 , wherein the enable controller sequentially enables each controllable local output buffer such that each of the one or more columns of the pixel array is driven according to a local output sequence. 
     
     
         9 . The column driver of  claim 8 , wherein the bus sequence is related to with the local output sequence. 
     
     
         10 . The column driver of  claim 1 , wherein the two or more controllable bus buffers includes a first controllable bus buffer having an input that receives a column data signal.