Passive matrix addressing is anaddressing scheme used in earlyliquid crystal displays (LCDs). It is a matrix addressing scheme, meaning that onlym + n control signals are required to address anm × n display. Apixel in a passive matrix must maintain its state without active driving circuitry until it can be refreshed again.

Thesignal is divided into a row orselect signal and a column orvideo signal. The selectvoltage determines the row that is being addressed and alln pixels on a row are addressed simultaneously. Whenpixels on a row are being addressed, aV_sel potential is applied, and all other rows are unselected with aV_unsel potential. The video signal or column potential is then applied with a potential for eachm columns individually. An on-switched (lit)pixel corresponds to aV_on, an off-switched (unlit) corresponds to aV_off potential.^[1]

The potential acrosspixel at selected rowi and columnj is

${\displaystyle V_{ij}=V_{\mathit{s}\mathit{e}\mathit{l}}-V_{\mathit{o}\mathit{n}\mathit{|}\mathit{o}\mathit{f}\mathit{f}}}$

and

${\displaystyle V_{ij}=V_{\mathit{u}\mathit{n}\mathit{s}\mathit{e}\mathit{l}}-V_{\mathit{o}\mathit{n}\mathit{|}\mathit{o}\mathit{f}\mathit{f}}}$

for the unselected rows.^[2]

This scheme has been expanded to define the limits of this type of addressing typical LCDs.^[3][4]

Passive matrix addressed displays, such asferroelectric liquid crystal displays, do not need the switch component of an active matrix display, because they have built-inbistability. Technology forelectronic paper also has a form of bistability. Displays with bistable pixel elements are addressed with a passive matrix addressing scheme, whereas TFT LCD displays are addressed usingactive addressing.

• Active matrix addressing
• Pixel geometry
• Liquid crystal display

• Digital imaging
• Liquid crystal displays