One point calibration integrated temperature sensor for wireless radio frequency applications

• US 7,461,972 B2
• Filed: 02/03/2006
• Issued: 12/09/2008
• Est. Priority Date: 02/08/2005
• Status: Active Grant

• Current Assignee: Altivera, LLC
• Original Assignee: Altivera, LLC
• Inventors: Cohen, Marc Harry
• Primary Examiner(s): VERBITSKY, GAIL KAPLAN
• Application Number:
  US11/347,088
• Publication Number:
  US 20060202821A1
• Time in Patent Office: 1,040 Days
• Field of Search: 374/1, 374/2, 374/100, 374/163, 374170-174, 374/183, 374/185, 374/179, 374117-119, 600/549, 600/474, 327/512, 327/513, 702/130, 702/133, 702/136, 702/139, 702/99, 340/870.17, 340/572.7
• US Class Current: 374/100
• CPC Class Codes: G01K 1/024 for remote indication
• CPC Class Codes: G01K 1/14 Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 15/00 Testing or calibrating of thermometers
• CPC Class Codes: G01K 7/01 using semiconducting elements having PN junctions G01K7/02, G01K7/16, G01K7/30 take precedence
• CPC Class Codes: G06K 19/0716 at least one of the integrated circuit chips comprising a sensor or an interface to a sensor
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card

Abstract

A low power analog linear temperature sensor integrateable with digital and/or analog circuits in CMOS fabrication processes. The sensor is accurately calibrateable at a single temperature that yields a linear relationship between measured differential voltage and temperature over a wide variety of temperature ranges. The sensor provides stable voltage and current references that are essential for wireless sensor platforms. There are many applications where sensors require stable voltage/current references and the physics of the sensor'"'"'s transduction mechanisms are themselves temperature dependent. Wireless platforms such as, but not limited to, passive RFID tags with the addition of on- or off-chip sensors provide a low cost solution for a variety of low cost sensor applications.

Claims

1. An analog linear temperature sensor which provides an output, said sensor comprising:

integrated temperature sensing elements configured to produce zero differential voltage at absolute zero temperature, wherein only a single measurement at a non-zero absolute temperature is required to calibrate the output over a range of temperatures;

said sensor being integrated into a computational device and configured to measure environmental temperature; and

said computational device being a cellular telephone, wherein said cellular telephone is configured to read temperature data from said sensor and data from at least one other sensor integrated into a radio frequency identifier (RFID) tag wherein said tag includes a wireless transceiver, said tag being attached to an object.

2. An analog linear temperature sensor which provides an output, said sensor comprising:

integrated temperature sensing elements configured to produce zero differential voltage at absolute zero temperature, wherein only a single measurement at a non-zero absolute temperature is required to calibrate the output over a range of temperatures;

said sensor being integrated into a computational device and configured to measure environmental temperature;

said computational device being a cellular telephone, wherein said cellular telephone is configured to read temperature data from said sensor and data from at least one other sensor integrated into a radio frequency identifier (RFID) tag wherein said tag includes a wireless transceiver, said tag being attached to an object; and

wherein said tag is configured as a passive diagnostic temperature skin patch sensor.