Temperature sensing systems and methods

• US 6,217,213 B1
• Filed: 05/26/1998
• Issued: 04/17/2001
• Est. Priority Date: 05/15/1990
• Status: Expired due to Fees

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Dallas Semiconductor Corporation (Analog Devices, Inc.)
• Inventors: Curry, Stephen M., Deierling, Kevin E., Bolan, Michael L., Payne, William Lee II, Kurkowski, Hal
• Primary Examiner(s): Bennett, G. Bradley
• Assistant Examiner(s): VERBITSKY, GAIL KAPLAN
• Application Number:
  US09/084,516
• Time in Patent Office: 1,057 Days
• Field of Search: 374/170, 374/178, 374/102, 368/200, 368/202, 327/512
• US Class Current: 374/178
• CPC Class Codes: G01K 1/028 arrangements for numerical indication
• CPC Class Codes: G01K 3/10 in respect of time, e.g. reacting only to a quick change of temperature
• CPC Class Codes: G01K 7/245 in an oscillator circuit
• CPC Class Codes: G06F 1/206 comprising thermal management
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: G06F 3/04897 Special input arrangements or commands for improving display capability
• CPC Class Codes: G06K 19/07 with integrated circuit chips
• CPC Class Codes: G06K 7/0021 for reading/sensing record carriers having surface contacts
• CPC Class Codes: G11C 5/066 Means for reducing external access-lines for a semiconductor memory clip, e.g. by multiplexing at least address and data signals
• 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 7/065 Differential amplifiers of latching type
• 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 23/58 Structural electrical arrangements for semiconductor devices not otherwise provided for , e.g. in combination with batteries H01L23/49593, H01L23/49596 take precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

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.

Claims

1. A temperature sensing apparatus, comprising:

at least one voltage generator for generating a substantially temperature-independent voltage potential, V;

a device coupled to said at least one voltage generator, for providing a current

signal with a magnitude, wherein said magnitude is substantially proportional to exp[−

(E_gap−

qV)/kT] where E_gap is the bandgap energy associated with said device, q is the Coulombic charge, V is said substantially temperature-independent voltage potential, k is the Boltzmann constant and T is an ambient temperature; and

a detector for sensing said current signal wherein said current signal varies in response to temperature changes.

3. The temperature sensing apparatus as recited in claim 1, wherein said device comprises a p-n junction coupled to said voltage generator, said voltage potential being applied across said junction to thereby generate said current signal.

4. The temperature sensing apparatus as recited in claim 1, wherein said device comprises a bipolar junction transistor coupled to said voltage generator, said transistor comprising a base, an emitter and a collector, said voltage potential being applied across a junction formed by said base and said emitter to thereby generate said current signal.

5. The temperature sensing apparatus as recited in claim 1, wherein said device and said detector are housed in a substantially token-shaped electronic module.

6. The temperature sensing apparatus as recited in claim 5, wherein said substantially token-shaped electronic module comprises:

at least a first conductive surface and a second conductive surface; and

an insulator disposed between said first and second conductive surfaces,

wherein said first and second conductive surfaces are shaped to form a substantially token-shaped body having a cavity disposed therein.

7. The temperature sensing apparatus as recited in claim 1, wherein said detector intermittently samples said current signal.

8. The temperature sensing apparatus as recited in claim 1, wherein said detector periodically samples said current signal.

9. The temperature sensing apparatus as recited in claim 1, wherein said voltage generator comprises a variable bandgap voltage source.

2. A temperature sensing apparatus having at least one voltage generator for generating a substantially temperature-independent voltage potential, V;

a device coupled to said at least one voltage generator, for providing a current signal with a magnitude, wherein said magnitude is substantially proportional to exp[−

(E_gap−

qV)/kT] where E_gap is the bandgap energy associated with said device, q is the Coulombic charge, V is said substantially temperature-independent voltage potential, k is the Boltzmann constant and T is an ambient temperature; and

a detector for sensing said current signal wherein said current signal varies in response to temperature changes wherein said detector comprises;

a current-to-voltage converter for converting said current signal into a voltage signal;

a voltage-to-frequency converter coupled to said current-to-voltage converter, said voltage-to-frequency converter for converting said voltage signal into a frequency; and

a counter coupled to said voltage-to-frequency converter, said counter for counting units of time, said units of time being generated in response to said frequency provided by said voltage-to-frequency converter.