Secure data entry device
First Claim
1. A secure data entry device comprising:
- a housing;
a protective enclosure located within said housing;
tamper sensitive circuitry located within said protective enclosure; and
tampering alarm indication circuitry arranged to provide an alarm indication in response to attempted access to said tamper sensitive circuitry, at least part of said tampering alarm indication circuitry being located within said protective enclosure, said tampering alarm indication circuitry comprising;
at least one conductor forming part of said protective enclosure;
a signal generator operative continuously, whether or not the secure data entry device is operative as a secured keypad device, to transmit a signal along said at least one conductor; and
a signal analyzer operative to receive said signal transmitted along said at least one conductor and to sense tampering with said at least one conductor, said signal analyzer being operative to sense said tampering by sensing changes in at least one of a rise time and a fall time of said signal, said at least one of said rise time and said fall time being less than a time normally required for said signal to traverse said at least one conductor.
8 Assignments
0 Petitions
Accused Products
Abstract
A secure data entry device including a housing, tamper sensitive circuitry located within the housing and tampering alarm indication circuitry arranged to provide an alarm indication in response to attempted access to the tamper sensitive circuitry, the tampering alarm indication circuitry including at least one conductor, a signal generator operative to transmit a signal along the at least one conductor and a signal analyzer operative to receive the signal transmitted along the at least one conductor and to sense tampering with the at least one conductor, the signal analyzer being operative to sense the tampering by sensing changes in at least one of a rise time and a fall time of the signal.
73 Citations
15 Claims
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1. A secure data entry device comprising:
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a housing; a protective enclosure located within said housing; tamper sensitive circuitry located within said protective enclosure; and tampering alarm indication circuitry arranged to provide an alarm indication in response to attempted access to said tamper sensitive circuitry, at least part of said tampering alarm indication circuitry being located within said protective enclosure, said tampering alarm indication circuitry comprising; at least one conductor forming part of said protective enclosure; a signal generator operative continuously, whether or not the secure data entry device is operative as a secured keypad device, to transmit a signal along said at least one conductor; and a signal analyzer operative to receive said signal transmitted along said at least one conductor and to sense tampering with said at least one conductor, said signal analyzer being operative to sense said tampering by sensing changes in at least one of a rise time and a fall time of said signal, said at least one of said rise time and said fall time being less than a time normally required for said signal to traverse said at least one conductor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
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Specification