Detecting multiple manual interactions

1. An apparatus for detecting multiple manual interactions, comprising:

a touch-pad for receiving multiple manual interactions;

a plurality of drive lines intersecting a plurality of scan lines, wherein each intersection between a drive line and a scan line includes an element of variable resistance;

a scanning processor for energizing said drive lines and monitoring said scan lines, said scanning processor is configured to sequentially monitor said scan lines, and ground remaining non-monitored scan lines during a first scanning operation,

said scanning processor is configured to apply a high substantially non-conducting impedance to said non-monitored scan lines during a second scanning operation, wherein said scanning processor is further configured to:

identify positions of manual interaction by performing said first scanning operation and said second scanning operation;

perform said first scanning operation at a first pressure resolution;

perform said second scanning operation at a second pressure resolution, wherein said first pressure resolution is lower than said second pressure resolution;

remove positions not identified by said first lower pressure resolution;

validate identified positions to identify potentially erroneous positions;

remove positions identified as erroneous; and

following said step of removing positions identified as erroneous, re-introduce removed positions when said removed positions are not directly adjacent to a correctly identified position such that said removed positions are determined as valid.

2. The apparatus of claim 1 , wherein said scanning processor identifies erroneous positions due to said drive lines and said scan lines creating parallel transmission paths.

3. The apparatus of claim 1 , wherein said scanning processor is configured to determine pressure values based on current for identified positions that have not been removed.

4. A method of detecting positions of multiple manual interactions on a touch-pad, comprising the steps of:

energizing a plurality of drive lines sequentially;

monitoring a plurality of intersecting scan lines sequentially to locate positions of interaction that may include erroneous positions, wherein remaining non-monitored scan lines are grounded during a first scanning operation and a high substantially non-conducting impedance is applied to said non-monitored scan lines during a second monitoring operation;

performing a validating operation to identify candidates for removal at said erroneous positions and removing erroneous positions located by the introduction of parallel transmission paths; and

re-introducing said candidates for removal when they are not directly adjacent to a correctly identified position such that said removed candidates are determined as valid,

said validating operation includes the step of performing an additional second scanning operation,

performing said first scanning operation at a first pressure resolution;

performing said second scanning operation at a second pressure resolution, said first pressure resolution is lower than said second pressure resolution; and

identifying positions not identified at said first lower pressure resolution as candidates for removal from a set of positions identified at said second higher pressure resolution.

5. The method of claim 4 , wherein said erroneous positions are identified due to said drive lines and said scan lines creating parallel transmission paths.

6. An apparatus for receiving data input from a user, in which a user applies a plurality of fingers on a touch-pad, said apparatus comprising a touch-pad and further comprising:

a plurality of drive lines that intersect with a plurality of scan lines to define an array;

a variable resistive element at each intersection of said array providing a variable electrically conductive path in response to an application of mechanical pressure; wherein

all non-scanning scan lines have their respective inputs made electrically conductive to ground during each performance of a first scanning operation and all non-scanning lines have their respective inputs made substantially non-conductive during each execution of a second scanning operation; said apparatus further comprising:

a processor, wherein said processor is configured to:

sequentially energize each of said drive lines;

perform said first scanning operation with a first pressure resolution to locate positions of true pressure application;

execute said second scanning operation with a second pressure resolution higher than said first pressure resolution rendering said second scanning operation prone to erroneous pressure identification;

rejecting pressure measurements from said second scanning operation at positions not located by said respective first scanning operation;

generate output signals based on pressure measurements that have not been rejected; and

re-introducing said rejected pressure measurements at positions that are not directly adjacent to a correctly identified position of true pressure application such that said rejected pressure measurements are determined as valid pressure measurements.

7. The apparatus of claim 6 , wherein said scanning processor identifies erroneous pressure measurements due to said drive lines and said scan lines creating parallel transmission paths.

8. The apparatus of claim 6 , wherein said scanning processor is configured to determine pressure measurements based on current for identified positions that have not been rejected.