EP0450910A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Temperature compensation circuit for hall effect element
Assignee: Honeywell Inc
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Filing: 1991-04-02
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Granted: —
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Expires: 2011-04-02
Abstract
Abstract A resistor formed in the same epitaxial layer of semiconductor material in which a Hall element (10) is formed is used to provide a temperature dependent voltage source which is inversely proportional to the resistance of a temperature sensitive load resistor (Rl₁, RL₂) on the Hall element output. A current mirror circuit is used to apply a current proportional to the current through the epitaxial layer resistor to the load resistor so that the voltage across through the load resistor varies in a direct relationship with the sensitivity of the Hall element.
Inventors
- 👤 Mark R. Plagens
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 11:05
CPC Classifications
G; G01; G01D; G01D3/00; G01D3/028; G01D3/036; G01D3/0365; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/07; Y; Y10; Y10S; Y10S323/00; Y10S323/907
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
125 words
A method of compensating for temperature dependent sensitivity in a Hall effect element formed in an epitaxial layer of semiconductor material wherein the output signal of the Hall effect element is detected by measuring the voltage across a temperature sensitive load resistor connected between an output of the Hall effect element and the Hall element bias voltage, the method characterised by the steps of: (a) providing a resistance element in which the electrical resistance varies with temperature sensitivity of the Hall element; (b) using the voltage across said resistance element to provide a voltage source which is inversely proportional to the resistance of the temperature sensitive load resistor; and (c) applying a current proportional to the current through said resistance element to said load resistor.
Claim 2
Dependent Claim
112 words
A circuit for sensing the effect of a magnetic field on a Hall effect element formed in a layer of epitaxial material, the circuit characterised by: (a) a temperature sensitive load resistor between the Hall element bias voltage and a Hall element output; (b) a temperature sensitive reference resistor providing a temperature sensitive reference voltage which is inversely proportional to the resistance of the temperature sensitive load resistor; and (c) current mirror circuit means providing a current proportional to the current through the reference resistor to the temperature sensitive load resistor so that voltage across the load resistor varies with temperature in direct relationship with the sensitivity of the Hall effect element.
Claim 3
Dependent Claim
28 words
A circuit according to Claim 2 characterised in that said reference resistor is formed in the same epitaxial layer of material in which the Hall element is formed.
Claim 4
Dependent Claim
59 words
A circuit according to Claim 2 or 3 characterised by: (d) a second temperature sensitive load resistor between the Hall element bias voltage and a second Hall element output; and (e) means for selectively alternately switching the current proportional to the current through the reference resistor to said temperature sensitive load resistor and said second temperature sensitive load resistor.
Claim 5
Dependent Claim
54 words
A circuit according to any of Claims 2 to 4 characterised by: (d) a second temperature sensitive load resistor between the Hall element bias voltage and a second Hall element output; and (e) means for selectively switching a current proportional to the current through the reference resistor to said second temperature sensitive load resistor.
Claim 6
Dependent Claim
263 words
A circuit for providing a temperature compensated output responsive to magnetic field strength the circuit characterised by: (a) a substrate having an epitaxial layer of semiconductor thereon; (b) a temperature sensitive Hall effect element formed in said epitaxial layer having a pair of bias terminals and a pair of output terminals between which a Hall voltage is generated when said Hall effect element is subjected to a magnetic field; (c) power supply means having a first and second terminals operatively connected across said bias terminals; (d) amplifier means operatively connected to said pair of output terminals to receive said Hall voltage, said amplifier means having a first and second output terminals; (e) a first temperature sensitive load resistor connected between said first terminal of said power supply means and said first output terminal of said amplifier means; (f) a second temperature sensitive load resistor connected between said first terminal of said power supply means and said second output terminal of said amplifier means; (g) current mirror circuitry operatively connected between said first and second terminals of said power supply means including a temperature sensitive resistor, the resistance of which is proportional to the temperature sensitivity of said Hall effect element, and a reference output terminal through which the current is proportional to the current through the reference resistor; and (h) switch means operative to selectively alternately connect said reference output terminal to said first and second output terminals of said amplifier means; whereby the voltage across said temperature sensitive load resistors is inversely proportional to the resistance of said temperature sensitive reference resistor.
Claim 7
Dependent Claim
29 words
A circuit according to Claim 6 characterised in that said temperature sensitive reference resistor is formed in the same epitaxial layer in which the Hall effect element is formed.
References Cited (Backward Citations)
No citation records indexed.
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