Secured keypad devices
A data entry device including a housing including a top housing portion including key apertures, a plurality of data entry keys mounted in the housing to have data entry key depression travel paths in the housing, the plurality of data entry keys being associated with a substrate, which is disposed below the top housing portion and anti-tampering electrical conductors arranged between the top housing portion and the substrate thereby to prevent unauthorized access to the substrate.
1. A data entry device comprising:
a housing including a top housing portion including key apertures;
a key mat defining a plurality of depressible keys which partially extend through said key apertures;
a resilient protective partial enclosure, including an anti-tampering grid formed of a multiplicity of interconnected anti-tampering electrical conductors on a top surface thereof, said resilient protective partial enclosure being formed with apertures aligned with said key apertures for permitting placement of said plurality of depressible keys therethrough;
a key contact pad, disposed within said resilient protective partial enclosure underlying said top surface, having an array of raised resilient domes with dome conductors being formed on corresponding bottom facing surfaces thereof;
an anti-tampering detection circuitry; and
an electrical circuit board disposed in predetermined spaced relationship with said key contact pad and defining a plurality of pairs of adjacent electrical contact pads, each pair of said plurality of pairs of adjacent electrical contact pads underlying a corresponding one of said dome conductors,
said key contact pad and said electrical circuit board being mutually arranged such that depression of one of said plurality of depressible keys causes the corresponding one of said dome conductors to establish electrical contact with and between a corresponding pair of said adjacent electrical contact pads lying thereunder and in registration therewith;
wherein a multiplicity of anti-tampering electrical conductors disposed below said adjacent electrical contact pads of said electrical circuit board are electrically connected to said anti-tampering detection circuitry; and
wherein said anti-tampering electrical conductors of said resilient protective partial enclosure are electrically connected to said anti-tampering electrical conductors disposed below said adjacent electrical contact pads of said electrical circuit board.
2. A data entry device according to claim 1 and wherein said key contact pad is flexible.
3. A data entry device according to claim 1 and wherein said anti-tampering electrical conductors of said resilient protective partial enclosure are disposed peripherally of said key contact pad.
4. A data entry device comprising:
a housing including a top housing portion including housing key apertures;
an anti-tamper board, including an anti-tampering grid formed of a multiplicity of interconnected anti-tampering electrical conductors underlying said top housing portion and including anti-tamper board key apertures in registration with said housing key apertures;
a key mat defining a plurality of depressible keys which partially extend through said housing key apertures and said anti-tamper board key apertures, said depressible keys having key conductors on bottom facing surfaces thereof;
an anti-tampering detection circuitry; and
an electrical circuit board disposed in predetermined spaced relationship with said key mat and defining a plurality of pairs of adjacent electrical contact pads, each pair of said plurality of pairs of adjacent electrical contact pads underlying a corresponding key conductor,
said key mat and said electrical circuit board being mutually arranged such that depression of one of said depressible keys causes the corresponding key conductor to establish electrical contact with and between a corresponding pair of said adjacent electrical contact pads lying thereunder and in registration therewith;
wherein said anti-tampering electrical conductors of said anti-tampering grid and a multiplicity of anti-tampering electrical conductors below said electrical circuit board are electrically connected to said anti-tampering detection circuitry; and
wherein said anti-tampering electrical conductors of said anti-tampering grid are electrically connected to said anti-tampering electrical conductors below said electrical circuit board.
5. A data entry device comprising:
a housing including a top housing portion including housing key apertures;
an anti-tamper board, including an anti-tampering grid formed of a multiplicity of interconnected anti-tampering electrical conductors underlying said top housing portion and including anti-tamper board key apertures in registration with said housing key apertures;
a key mat defining a plurality of depressible keys which partially extend through said housing key apertures and said anti-tamper board key apertures;
a flexible resilient protective element, including an anti-tampering grid formed of a multiplicity of interconnected anti-tampering electrical conductors;
an anti-tampering detection circuitry;
a key contact pad below said flexible resilient protective element and having an array of raised resilient domes with dome conductors being formed on corresponding bottom facing surfaces thereof; and
an electrical circuit board disposed in predetermined spaced relationship with said key contact pad and defining a plurality of pairs of adjacent electrical contact pads, each pair of said plurality of pairs of adjacent electrical contact pads underlying a corresponding dome conductor,
said key contact pad and said electrical circuit board being mutually arranged such that depression of one of said depressible keys causes the corresponding dome conductor to establish electrical contact with and between a corresponding pair of said plurality of pairs of adjacent electrical contact pads lying thereunder and in registration therewith;
wherein said anti-tampering electrical conductors of said anti-tamper board and said anti-tampering electrical conductors of said flexible resilient protective element are electrically connected to said anti-tampering detection circuitry;
wherein said anti-tampering electrical conductors of said anti-tamper board are electrically connected to said anti-tampering electrical conductors of said flexible resilient protective element.