Dallas Semiconductor Corporation

Stephen M Curry

Michael L Bolan

Robert D Lee

Hal Kurkowski

Kevin E Deierling

Donald W Loomis

Wendell L Little

William L Payne, Ii

Christopher W Fox

Donald R Dias

Francis A Scherpenberg

Donald R Diaz

Gary V Zanders

Guenter H Lehmann

Stephen N Grider

Bradley M Harrington

Steven N Hass

Peter Schweitzer

David A Bunsey

Scott J Curry

Mark L Thrower

Don Folkes

Guenther H Lehmann

Bryan M Armstrong

Steven N Grider

Ricky D Fieseler

Kevin E Peirling

A microcontroller communicating via a data path and an address path with a memory block containing encrypted contents, the microcontroller including the capability for detecting resets effectuated in the wake of an unauthorized attempt to gain access to the encrypted contents and the capability of evading such an unauthorized attempt.

Systems and methods for protecting access to encrypted information

The present invention relates to an electronic module used for secure transactions. More specifically, the electronic module is capable of passing encrypted information back and forth between a service provider's equipment via a secure, encrypted technique so that money and other valuable data can be securely passed electronically. The module is capable of being programmed, keeping track of real time, recording transactions for later review, and creating encryption key pairs.

Apparatus for transfer of secure information between a data carrying module and an electronic device

A temperature-controlled counter/clock arrangement is provided where th rate or frequency of the counting is temperature dependent. This allows for a measuring of thermal accumulation and/or history. The temperature sensing is based upon the use of the varying current that will flow through a toward biased semiconductor diode. In one embodiment a constant voltage source is used so that the current variation will follow Arrhenius's law.

Temperature sensing systems and methods

A secure monetary system comprises an electronic module and equipment to access the electronic module. The electronic module comprising a substantially token-shaped module and secure memory circuitry to store monetary information. The secure memory positioned in the substantially token-shaped module. The equipment accesses and manipulates the monetary information stored in the memory in the electronic module. The equipment comprises memory to store control and encryption programs and the memory is coupled to a microprocessor, which is also coupled to the electronic module and a control panel. The microprocessor is secure.

Secure storage of monetary equivalent data systems and processes

A method of communicating information between a host device and a potentially portable module device which measures thermal accumulation over time via a temperature controlled counter. The temperature controlled counter may operate using substantially Arrhenius' law. The host device communicates with the portable module via a single wire bidirectional data bus. The single wire bus and one-wire communication protocol allows data flow between a host and a plurality of devices connected to the single wire bus. The single wire bus allows for a great versatility of uses for the portable module.

Method of communicating over a single wire bus between a host device and

A system architecture which provides efficient data communication, over a one-wire bus, with a portable data module which does not necessarily include any accurate time base whatsoever. The time base in the module can be extremely crude (e.g. more than 4:1 uncertainty). An open-collector architecture is used, with electrical relations defined to absolutely minimize the drain on the portable module's battery. The protocol has been specified so that the module never sources current to the data line, but only sinks current. The protocol includes signals for read; write-zero; write-one; and reset. Each one-bit transaction is initiated by a falling edge from the host. The time base in the module defines a delay, after which (in write mode) the module tests the data state of the data line. In read mode, after a falling edge the module does or does not turn on its pull-down transistor, depending on the data value. Thus, the host system, after the falling edge, attempts to pull the data line high again, and then tests the potential of the data line to ascertain the data value.

Single wire data communication method

The present invention relates to an electronic module used for secure transactions. More specifically, the electronic module is capable of passing information back and forth between a service provider's equipment via a secure, encrypted technique so that money and other valuable data can be securely passed electronically. The module is capable of being programmed, keeping track of real time, recording transactions for later review, and creating encryption key pairs.

Method, apparatus, system and firmware for secure transactions

Transaction system and method

A secure electronic data module containing a monolithic semiconductor chip of the type having a memory that is protected by a combination of hardware and software mechanisms such that unauthorized access to the data stored in the memory is prevented. The monolithic semiconductor chip comprises a plurality of solder bumps for attaching the chip to a substrate that may be a printed circuit board or another chip; a multi-level interlaced power and ground lines using minimum geometries; and a detection circuit block for detecting an external trip signal that may be produced by a pre-specified change in an operating condition brought on by unauthorized accessing, or an internal trip signal that may be produced by shorting of power and ground lines or by a change in an oscillator's frequency, also associated with or appurtenant to unauthorized accessing of the secure memory.

Microcircuit with memory that is protected by both hardware and software

In a data bus environment where a host device and a plurality of other devices are connected to the bus, the time required for the first and the last device to respond to a host request is measured. Once the time required between the first and the last response is known, then a read/write window time can be minimized thereby increasing the speed of communication over the data bus.

Method and system for measuring a maximum and minimum response time of a

A secured metal token using a single wire communication system is employed to dispense units of value and to provide a secure storage device for controlling the dispensing of articles or service items. The metal token can be formed of two pieces with a simplified electronic circuit inside which can contain units of value for the dispensing of items using the memory within the metal token as a secure vault. The token uses a simple two wire (ground and combined clock/data) arrangment. As goods are purchased or services rendered the value of those good or services is deducted from a prestored amount within the token.

Metal token having units of value stored therein using a single wire

The present invention relates to system, apparatus and method for communicating valuable data from a portable module to another module via an electronic device. More specifically, the disclosed system, apparatus and method are useful for enabling a user to fill a portable module with a cash equivalent and to spend the cash equivalent at a variety of locations. The disclosed system incorporates an encryption/decryption method.

Transfer of valuable information between a secure module and another

The present invention rotates to system, apparatus and method for communicating valuable data from a portable module to another module via an electronic device. More specifically, the disclosed system, apparatus and method are useful for enabling a user to fill a portable module with a cash equivalent and to spend the cash equivalent at a variety of locations. The disclosed system incorporates an encryption/decryption method.

A communication circuit is provided in which reads from a device are controlled by sensing a transition by a host communicating with a device. The device then accepts a one which holds the line high for a predetermined time period or accepts a zero when the line is held high for a different time period. The sending of data is accomplished in a symmetrical relationship by having the device after the host pulls the line high by either by allowing the line to remain high or forcing the line to ground within the requisite time periods. This allows the 'slave' device to consume almost no power in either the read or the write modes.

Single wire communication system

A portable electronic data module for secure transactions, the electronic data module having a random number generator and an optimized co-processor for producing unbreakable key sets for a two-key cryptosystem. A real-time clock is sampled depending upon an external random event series such as power-ups of the data module by a host apparatus, and based upon the contents of the sample thus obtained, the entropy of a previously-loaded accumulator is further enhanced to achieve a pool of true random numbers. By repeatedly requesting random bytes of information from said pool of random numbers, large random numbers are created which are then rendered prime and used for key set creation.

Growing community of inventors

Dallas, TX, United States of America

Stephen M Curry