Environmental condition sensor device and method

• US 6,587,807 B2
• Filed: 07/23/2002
• Issued: 07/01/2003
• Est. Priority Date: 10/07/1992
• Status: Expired due to Fees

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Dallas Semiconductor Corporation (Analog Devices, Inc.)
• Inventors: Lee, Robert D., Kurkowski, Hal, Awtrey, James D.
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): Raymond, Edward
• Application Number:
  US10/201,355
• Publication Number:
  US 20020177970A1
• Time in Patent Office: 343 Days
• Field of Search: 702/130, 702/133, 702/99, 702/136, 236/1.B, 236/1.C, 236/91.R, 236/9.H, 236/94, 374/101, 374/109, 374/113, 374/132, 374/163, 374/166, 374/167, 320/144, 320/153, 320/154, 324/425, 324/426, 324/431, 324/224, 324/760, 324/670, 324/685, 324/721, 403/28, 337/300, 732/35, 737/66
• US Class Current: 702/130
• CPC Class Codes: G01K 7/13 Circuits for cold-junction compensation

Abstract

A device and method for measuring temperature is disclosed. The device, for example, can include a thermocouple configured to generate a voltage indicative of a junction temperature; a memory device configured to store a unique device ID and to store data; a logic unit connected to the thermocouple and the memory device; an I/O interface connected to the logic unit, the I/O interface configured to communicate with a computer system; and an internal temperature sensor connected to the logic unit, the internal temperature sensor configured to determine a cold junction temperature.

Claims

1. A system for monitoring environmental conditions, the system comprising:

a computer;

a data line connected to the computer;

a reference line connected to the computer;

at least one environmental monitoring device (EMD) connected to the data line and the reference line;

wherein said at least one EMD communicates with the computer over the data line in digital format and wherein each EMD is separately and uniquely digitally addressable on at least one bus by said computer;

further wherein said at least one EMD comprises a memory capable of storing a unique device ID and calibration data.

2. The system of claim 1, wherein said at least one EMD comprises:

a temperature sensor.

3. The system of claim 2, wherein the temperature sensor comprises:

a thermocouple.

4. The system of claim 3, wherein said at least one EMD comprises:

a cold junction temperature sensor.

5. The system of claim 1, wherein said at least one EMD comprises:

an external humidity sensor element.

6. The system of claim 1, wherein the first EMD comprises:

a pressure sensor.

7. The system of claim 1, wherein the first EMD comprises:

a solar radiance sensor.

8. The system of claim 1, wherein the first EMD comprises:

a photocell sensor.

9. The system of claim 1, wherein the first EMD is configured to receive digital data from the computer.

10. The system of claim 1, wherein the first EMD comprises:

a thermistor.

11. The system of claim 1, wherein said data line and said reference line are selected from the group of a hard wired line, an RF link or an optical fiber.