CapacitorStack Class Reference

Draws the layout of a compact capacitor or a matrix of adjacent identical capacitors. More...

Inheritance diagram for CapacitorStack:

Public Member Functions
	__init__ (self, device, capacitance, capacitorType, abutmentBoxPosition, nets, unitCap=0, matrixDim=[1, 1], matchingMode=False, matchingScheme=[], dummyRing=False, dummyElement=False)
	This is the class constructor.
	setRules (self)
	Selects technological rules according to the capacitor type.
	__isUnitCap__ (self)
	__isMatchingSchemeOK__ (self)
	capacitorIdOccurence (self, capacitorIdentifier)
	create (self, bbMode=False)
	Draw the compact or matrix of capacitors.
	capacitorLine (self, dy, abutmentBox_spacing, matchingSchemeRowIndex=0)
	Iteratively draws a horizontal or vertical line of capacitors according to the direction parameter.
	capacitorMatrix (self, abutmentBox_spacing=0)
	Draws a matrix of identical capacitors.
	drawAbutmentBox (self, abutmentBox_spacing=0)
	Draws the abutment box of the matrix or campact capacitor.
	drawBottomPlatesRLayers (self, bottomPlateRLayer, drawnCapacitor)
	Draws the routing layers connecting the bottom plate in the matrix of capacitors.
	drawTopPlatesRLayers (self, topPlateRLayer, drawnCapacitor)
	Draws the routing layers connecting the top plates in the matrix of capacitors.
	getVerticalRoutingTrack_width (self)
	getMatrixDim (self)
	getMatchingScheme (self)
Public Member Functions inherited from CapacitorUnit
	__init__ (self, device, capacitorType, abutmentBoxPosition, capacitance=0, capDim={})
	This is the class constructor.
	__setCapacitorPerUnit__ (self, capacitorType)
	Sets the area and perimeter capacitances as specified in 350 nm AMS technology and according to capacitorType (MIM or PIP).
	__computeCapDim__ (self, capacitance, capacitorType)
	Computes width and length of the capacitor.
	__isCapacitorUnitOK__ (self, capDim)
	Checks if the computed capacitor dimensions exceed or are less than maximum and minimum limits, respectively, as specified in technology rules.
	getCapacitorType (self)
	getMaximumCapWidth (self)
	getMinimumCapWidth (self)
	getLayers (self)
	Loads the technology file then extracts the adequate layers according to the capacitor type (MIM or PIP).
	drawCapacitor (self, layerDict, t, b)
	Draws all layout physicial layers of the capacitor.
	computeBottomPlateCuts (self)
	Computes needed parameters to draw bottom plate cuts in its exact position, including :
	computeTopPlateCuts (self)
	Computes needed parameters to draw top plate cuts in its exact position, including :
	drawOnePlate (self, layer, net, boxDimensions)
	Draws the top or bottom plate through inflation of the Box under it.
	drawBottomPlateCut (self, layer, b)
	Draws the required cuts to connect the bottom plate.
	drawTopPlateCut (self, layer, t)
	Draws the top plate's cuts after computing the maximal number of cuts that can be placed and its exact enclosure in the top plate.
	drawRoutingLayers (self, bottomPlateLayer, topPlateLayer, t, b)
	Draws the routing layers of both bottom and top plates after computing widths and the exact position of these layers.
	cutMaxNumber (self, width_layer, width_cut, spacing_cut, enclosure_cut)
	Computes the maximal number of cuts to be placed on a layer of width width_layer considering specifications such as the spacing between the cuts, its width and its enclosure in the layer.
	cutLine (self, net, layer, firstCutXCenter, firstCutYCenter, width_cut, height_cut, spacing_cut, cutNumber, direction)
	Creates a horizontal or vertical line of contacts according to the specified direction.
	cutMatrix (self, net, layer, firstCutXCenter, firstCutYCenter, width_cut, height_cut, spacing_cut, cutColumnNumber, cutRowNumber)
	Creates a matrix of cuts by vertically stacking horizontal lines of identical cuts.
	getBottomPlateYMax (self)
	getBottomPlateLeftCutXMin (self)
	getBottomPlateLeftCutYMin (self)
	getBottomPlateLeftCutYMax (self)
	getBottomPlateRightCutXMin (self)
	getBottomPlateRightCutYMin (self)
	getBottomPlateRightCutYMax (self)
	getBotPlateLeftRLayerXMax (self)
	getBottomPlateRightCutYCenter (self)
	getBotPlateLeftRLayerXMin (self)
	getBotPlateRLayerYMin (self)
	getBotPlateRLayerYMax (self)
	getBotPlateRLayerWidth (self)
	getBotPlateRightRLayerXCenter (self)
	getBotPlateLeftRLayerXCenter (self)
	getTopPlateRLayerYMin (self)
	getTopPlateRLayerYMax (self)
	getTopPlateRLayerWidth (self)
	getTopPlateRLayerXCenter (self)
	getTopPlateRLayerXMin (self)
	getTopPlateRLayerXMax (self)

Detailed Description

Draws the layout of a compact capacitor or a matrix of adjacent identical capacitors.

The matrix can be composed of one type of capacitors, either Poly-Poly or Metal-Metal in 350 nm AMS CMOS technology. When matching mode is off, every adjacent plates of any consecutive elementary capacitors are connected to each other using vertical routing layers. Otherwise, when matching mode is on, any of elementary capacitors can belong to, or according to the entered matching scheme. Thus, routing is not done in this class. In both modes, the complete routing process is done using the RoutCapacitor class.

Constructor & Destructor Documentation

__init__()

__init__	(		self,
			device,
			capacitance,
			capacitorType,
			abutmentBoxPosition,
			nets,
			unitCap = 0,
			matrixDim = [1,1],
			matchingMode = False,
			matchingScheme = [],
			dummyRing = False,
			dummyElement = False )

This is the class constructor.

Basically, the class there are three categories of attributes. There are the ones related to the capacitor caracteristics, its type, dimensions. Also, there are attributes to parametrize the class into matching mode or not and there are other attributes realted to the layout varibales. The class has defaut input values, thus, in this constructor, there are two "sub-constructors" according to the entered input parameters. The class attributes are :

Parameters

device	The Hurricane AMS device into which the layout is drawn.
capacitance	The value of the capacitor, expressed in femto Farad (fF).
capacitorType	Can be MIM or PIP type capacitor.
abutmentPosition	Refers to the abscissa (XMin) of the bottom left corner of the abutment Box.
abutmentBoxYMin	Refers to the ordinate (YMin) of the bottom left corner of the abutment Box.

Except the two last arguments, all the parameters are common with the CapacitorUnit class because the CapacitorStack constructor calls the mother class constructor to create either a compact capacitor of capacitance value or rowNumber* columnNumber unity capacitors.

Parameters

rowNumber	Number of rows in the matrix of capacitors.
columnNumber	Number of columns in the matrix of capacitors.

References __areInputDataOK__(), CapacitorUnit.__computeCapDim__(), __initGivenNonZeroUnitCap__(), __initGivenNonZeroUnitCapInMatchingMode__(), __initGivenZeroUnitCap__(), __initGivenZeroUnitCapInMatchingMode__(), CapacitorUnit.abutmentBox, abutmentBox_spacing, abutmentBoxPosition, capacitorsNumber, CapacitorUnit.capacitorType, compactCapDim, CapacitorUnit.device, Stack.device, doMatrix, dummyElement, dummyRing, dummyRingPosition, matchingMode, matchingScheme, matrixDim, nets, unitCapDim, and vRoutingTrack_width.

Member Function Documentation

setRules()

setRules

(

self

)

Selects technological rules according to the capacitor type.

Returns

a dictionary with rules labels as keys and rules as values. Example of technology rules are :

• minimum spacing between cuts or metals,
• minimum width of a plate, a cut or a routing metal.
• etc. Every rule takes two possible value according to the capacitor type (MIM or PIP). Therefore, dictionary keys are generic and its values are specific to the capacitor type.

Remark:

An exception is raised if the entered capacitor type is unknown.

Reimplemented from CapacitorUnit.

Reimplemented in RoutMatchedCapacitor, and VerticalRoutingTracks.

References CapacitorUnit.__computeCapDim__(), __initMatrixMode__(), CapacitorUnit.__isCapacitorUnitOK__(), abutmentBox_spacing, capacitance, capacitorIdOccurence(), capacitorsNumber, CapacitorUnit.capacitorType, compactCapDim, computeUnitCap(), doMatrix, evaluateUnitCap(), matchingScheme, matrixDim, minEnclosure_hRoutingLayer_topPlate_cut, minEnclosure_vRoutingTrackCut, minSpacing_vRoutingTrack, minSpacing_vRoutingTrackCut, minWidth_hRoutingLayer_topPlate_cut, minWidth_vRoutingTrack, minWidth_vRoutingTrackCut, unitCapacitance, unitCapDim, and vRoutingTrack_width.

__isUnitCap__()

__isUnitCap__

(

self

)

Returns

True if the drawn capacitor is a compact one. This function is useful when an instance is called in another class. Example : when the matrix or the compact capacitors are to be fully routed.

Referenced by RoutMatchedCapacitor.route().

__isMatchingSchemeOK__()

__isMatchingSchemeOK__

(

self

)

Returns

True if the matching scheme specifications are correct. Specifications are :

• Similar number of elements as total number of elementary capacitor in the matrix.
• Equal number of affected capacitors to C1 as to C2.
• Capacitor identifiers equal to '1' or '2' only.
• Otherwise, the function returns False.

References matchingScheme, and matrixDim.

Referenced by capacitorIdOccurence().

capacitorIdOccurence()

capacitorIdOccurence	(		self,
			capacitorIdentifier )

Returns

occurence of capacitor identifier in the entered matching scheme. This is useful to verify that self.matchingScheme is correct.

References __areMatrixDimOK__(), __isMatchingSchemeOK__(), capacitorsNumber, dummyElement, dummyRing, matchingMode, matchingScheme, matrixDim, and nets.

Referenced by setRules().

create()

create	(		self,
			bbMode = False )

Draw the compact or matrix of capacitors.

First, . Second, . Finally, .

Reimplemented from CapacitorUnit.

Reimplemented in VerticalRoutingTracks.

References __initMatchingMode__(), abutmentBox_spacing, abutmentBoxPosition, capacitance, capacitorMatrix(), CapacitorUnit.capacitorType, computeBondingBoxDimensions(), CapacitorUnit.device, Stack.device, doMatrix, CapacitorUnit.drawAbutmentBox(), drawBottomPlatesRLayers(), drawCapacitorStack(), drawTopPlatesRLayers(), dummyRing, matchingMode, matrixDim, nets, and CapacitorUnit.setRules().

Referenced by capacitorLine(), and capacitorMatrix().

capacitorLine()

capacitorLine	(		self,
			dy,
			abutmentBox_spacing,
			matchingSchemeRowIndex = 0 )

Iteratively draws a horizontal or vertical line of capacitors according to the direction parameter.

An exception is raised if the specified direction is different from {'horizontal','vertical'}. At every iteration, an instance of the CapacitorUnit class is created and its layout is drawn.

Returns

a list containing the drawn capacitors.

Parameters

dy	the vertical position of the first cut in cut line.

Remarks

An exception is raised if the specified direction is different from {'horizontal','vertical'}

References abutmentBoxPosition, CapacitorUnit.capacitorType, create(), createElementInCapacitorLine(), CapacitorUnit.device, Stack.device, dummyRing, matchingMode, matchingScheme, matrixDim, nets, and unitCapacitance.

Referenced by capacitorMatrix().

capacitorMatrix()

capacitorMatrix	(		self,
			abutmentBox_spacing = 0 )

Draws a matrix of identical capacitors.

The matrix is iterativelly constructed. At every iteration, a new horizontal line of capacitors is drawn.

Returns

a nested list of elementary capacitors.

References abutmentBox_spacing, abutmentBoxPosition, capacitorLine(), CapacitorUnit.capacitorType, create(), CapacitorUnit.device, Stack.device, dummyRing, getCapDim(), matrixDim, nets, and unitCapacitance.

Referenced by create().

drawAbutmentBox()

drawAbutmentBox	(		self,
			abutmentBox_spacing = 0 )

Draws the abutment box of the matrix or campact capacitor.

Reimplemented from CapacitorUnit.

References CapacitorUnit.abutmentBox, abutmentBox_spacing, abutmentBoxPosition, CapacitorUnit.computeAbutmentBoxDimensions(), CapacitorUnit.device, and Stack.device.

drawBottomPlatesRLayers()

drawBottomPlatesRLayers	(		self,
			bottomPlateRLayer,
			drawnCapacitor )

Draws the routing layers connecting the bottom plate in the matrix of capacitors.

First, the relative positions of the routing layer is of the is extracted from the elementary capacitor instance. Then, its width is computed in a way to connect adjacent plates. Then, the routing layers are iterativelly drawn. The two borders are .

References CapacitorUnit.getBotPlateLeftRLayerXMax(), CapacitorUnit.getBotPlateRLayerWidth(), CapacitorUnit.getBotPlateRLayerYMax(), CapacitorUnit.getBottomPlateLeftCutXMin(), CapacitorUnit.getBottomPlateRightCutXMin(), matrixDim, and nets.

Referenced by create().

drawTopPlatesRLayers()

drawTopPlatesRLayers	(		self,
			topPlateRLayer,
			drawnCapacitor )

Draws the routing layers connecting the top plates in the matrix of capacitors.

First, the relative positions of the routing layers is of the is extracted from the elementary capacitor instance. Then, its width is computed in a way to connect adjacent plates. Then, the routing layers are iterativelly drawn. The two borders are .

Remarks

An exception is raised if the number of rows in the matrix is lower than 2.

References CapacitorUnit.getTopPlateRLayerWidth(), CapacitorUnit.getTopPlateRLayerXCenter(), CapacitorUnit.getTopPlateRLayerYMax(), CapacitorUnit.getTopPlateRLayerYMin(), matrixDim, and nets.

Referenced by create().

getVerticalRoutingTrack_width()

getVerticalRoutingTrack_width

(

self

)

Returns

The width of the vertical routing tracks in matching mode.

Remark:

This function is useful in matching mode, ie., in RoutCapacitor class, when routing the two capacitors.

getMatrixDim()

getMatrixDim

(

self

)

Returns

A dictionary contaning capacitor matrix's dimensions

References compactCapDim, and doMatrix.

getMatchingScheme()

getMatchingScheme

(

self

)

Returns

the matching scheme. The function is useful in RoutMatchedCapacitor class to load self.matchingScheme attribute.

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The documentation for this class was generated from the following file:

• capacitormatrix.py