Parasitically powered microprocessor capable of transmitting data over a single data line and ground

• US 6,412,072 B2
• Filed: 02/05/2001
• Issued: 06/25/2002
• Est. Priority Date: 07/20/1995
• Status: Expired due to Term

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Dallas Semiconductor Corporation (Analog Devices, Inc.)
• Inventors: Grider, Stephen N., Bartling, James E., Little, Wendell, Curiger, Andreas, Harrington, Bradley M., Bunsey, David A., Liu, Shyun
• Primary Examiner(s): LE, DIEU MINH T
• Application Number:
  US09/777,031
• Publication Number:
  US 20010011353A1
• Time in Patent Office: 505 Days
• Field of Search: 713/200, 714/5, 714/29, 711/115, 710/7, 710/11, 710/20, 710/27, 326/8, 365/226
• US Class Current: 726/34
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G06F 21/602 Providing cryptographic facilities or services
• CPC Class Codes: G06F 21/72 in cryptographic circuits
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: G06F 21/81 by operating on the power supply, e.g. enabling or disabling power-on, sleep or resume operations
• CPC Class Codes: G06F 21/86 Secure or tamper-resistant housings
• CPC Class Codes: G06F 21/87 by means of encapsulation, e.g. for integrated circuits
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: G06F 2221/2153 Using hardware token as a secondary aspect
• CPC Class Codes: G06F 7/588 Random number generators, i.e. based on natural stochastic processes
• CPC Class Codes: G06F 9/30134 Register stacks; shift registers
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/40975 using encryption therefor
• CPC Class Codes: G07F 7/082 Features insuring the integrity of the data on or in the card
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G11C 5/06 Arrangements for interconnecting storage elements electrically, e.g. by wiring
• CPC Class Codes: G11C 5/143 Detection of memory cassette insertion or removal; Continuity checks of supply or ground lines; Detection of supply variations, interruptions or levels G11C5/148 takes precedence; Switching between alternative supplies G11C5/141 takes precedence
• CPC Class Codes: G11C 7/24 Memory cell safety or protection circuits, e.g. arrangements for preventing inadvertent reading or writing; Status cells; Test cells
• CPC Class Codes: G11C 8/20 Address safety or protection circuits, i.e. arrangements for preventing unauthorized or accidental access
• CPC Class Codes: H01L 2224/16225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 23/57 : Protection from inspection, reverse engineering or tampering
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H04L 25/026 : Arrangements for coupling transmitters, receivers or transceivers to transmission lines; Line drivers duplexing arrangements H04L5/14
• CPC Class Codes: Y10S 257/922 : with means to prevent inspection of or tampering with an integrated circuit, e.g. "smart card", anti-tamper

Abstract

An electronic module having at least a microprocessor and co-processor on a single integrated circuit. The electronic module can be contained in a small housing. The electronic module provides secure bidirectional data communication via a data bus. The electronic module may include an integrated circuit comprising a microprocessor, and a co-processor adapted to handle 1,024-bit modulo mathematics primarily aimed at RSA calculations. The electronic module is preferably contained in a small token sized metallic container and will preferably communicate via a single wire data bus which uses a one-wire protocol.

Claims

1. A electronic module comprising:

an interface for bidirectionally interfacing said electronic circuit to another electronic device via a single data wire and a reference connection;

a UART connected to said interfce;

a microprocessor circuitry connected to said UART;

a memory circuit connected to said one wire UART and to said microprocessor core circuit;

a circuit as part of said interface capable of sinking current on said single data line to said reference connection.

2. A circuit as in claim 1 wherein said reference connection comprises:

a grounding point.

3. A circuit as in claim 1 wherein said microprocessor core obtains power to operate said core from said single wire data wire.