The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 1978
Filed:
Nov. 14, 1977
Paul M Helmstetter, Littleton, CO (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A capacitive integrator passes a current through a non-linearity compensating transistor, a thermistor, and an analog output amplifier and resistor so that the value of the current and the value of the voltage across the resistor are proportional to the thermistor temperature. A comparator detects each passage of the integrator output voltage above zero, and causes the output of a flip-flop to go high upon such passage for a fixed time period during which an opposing current is passed through the integrator capacitor to drive the integrator output voltage below zero. The resulting pulses in the flip-flop output are counted by a presettable counter for a predetermined counting period to give a count which is proportional to the thermistor current and temperature. This count is decimally displayed and is made numerically equal to the thermistor temperature according to any desired temperature scale by suitably selecting the length of the counting period and the preset count of the counter.