Temperature measurement apparatus
First Claim
Patent Images
1. A temperature measurement apparatus comprising:
- a temperature sensitive device;
an electric circuit for producing output signals responding to electrical states of said temperature sensitive device;
a reference resistor of a known temperature coefficient which is connected in said electric circuit to produce a reference output signal at a predetermined reference environmental temperature and at a reference voltage of a power source;
a memory for memorizing said reference output signal;
a control circuit for alternatively switching to produce output signals for said temperature sensitive device and for said reference resistor; and
a calibration circuit for calibrating a measurement error due to variation from said environmental temperature and a power source voltage by use of said memorized reference output signal and said output signals for said temperature sensitive device and said reference resistor,said calibration circuit for performing an arithmetic calculation ##EQU10## where VcO is said reference output signal, Vc and Vm are said output signals for said reference resistor and said temperature sensitive device, respectively, and 1+f(T) represents a function representing thermal characteristics of said temperature sensitive device at a temperature T normalized with respect to said reference temperature.
0 Assignments
0 Petitions
Accused Products
Abstract
A temperature measurement apparatus comprising a temperature sensitive device such as thermistor and a reference resistor of small temperature coefficient of resistance, which are alternatively connected to an electric circuit which produces an output signal responding to change of resistance, and the apparatus comprises a memory which memorizes a reference output signal by a reference resistor at a predetermined reference environmental temperature and a reference voltage of a power source, and a calibration is made to a measured temperature value by use of said memorized reference output signal.
120 Citations
3 Claims
-
1. A temperature measurement apparatus comprising:
-
a temperature sensitive device; an electric circuit for producing output signals responding to electrical states of said temperature sensitive device; a reference resistor of a known temperature coefficient which is connected in said electric circuit to produce a reference output signal at a predetermined reference environmental temperature and at a reference voltage of a power source; a memory for memorizing said reference output signal; a control circuit for alternatively switching to produce output signals for said temperature sensitive device and for said reference resistor; and a calibration circuit for calibrating a measurement error due to variation from said environmental temperature and a power source voltage by use of said memorized reference output signal and said output signals for said temperature sensitive device and said reference resistor, said calibration circuit for performing an arithmetic calculation ##EQU10## where VcO is said reference output signal, Vc and Vm are said output signals for said reference resistor and said temperature sensitive device, respectively, and 1+f(T) represents a function representing thermal characteristics of said temperature sensitive device at a temperature T normalized with respect to said reference temperature. - View Dependent Claims (2, 3)
-
Specification
-
- Resources
Litigation Campaign Assessment
Thank you for your request. You will receive a custom alert email when the Litigation Campaign Assessment is available.
×
-
Current AssigneeMatsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
-
Original AssigneeMatsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
-
InventorsIshiwatari, Hiromasa, Yamada, Yoshinori
-
Primary Examiner(s)Woodiel, Donald O.
-
Application NumberUS05/964,520Time in Patent Office580 DaysField of Search73/362.5, 73/1 F, 73/362 AR, 73/708, 364/557US Class Current374/183CPC Class CodesG01D 3/0365 the undesired influence bei...G01K 1/20 Compensating for effects of...G01K 7/24 in a specially-adapted circ...
