US 6,604,423 B1 · Pressure sensor, pressure sensor control apparatus, and pressure sensor system

Abstract

The type of a pressure sensor is automatically identified even when the input/output lines of the pressure sensor are three lines, i.e., power source lines (two of + and −) and a voltage output line for outputting a voltage corresponding to an applied pressure. The current value Ip, which flows through the power source lines of the pressure sensor, is made to be a different value depending on each type of the pressure sensor. A voltage value Vr (Vr=Ip×Rr, where Rr is a resistance value of a resistor) is measured by using a differential amplifier, and the voltage value Vr is compared with a voltage range previously recorded in ROM. Accordingly, the type of the pressure sensor can be automatically identified by using a microcomputer.

Claims13

Dependent claims

A pressure sensor comprising:

three terminals, the three terminals comprising first and second input terminals for connection to a DC power source, and a third signal output terminal for outputting a signal corresponding to an applied pressure;
and
power source current-setting means for setting a power source current value flowing through said DC power source input terminal as a consumption current flowing through said pressure sensor, said power source current value being different depending on a type of said pressure sensor.

A pressure sensor control apparatus to be connected with DC power source input terminals composed of two terminals, and a signal output terminal for outputting a signal corresponding to an applied pressure, of a pressure sensor, for performing a predetermined process in accordance with said signal output, said pressure sensor control apparatus comprising:

power source current value-detecting means for detecting a power source current value set by said pressure sensor as a consumption current flowing through said DC power source input terminals;
and
type-identifying means for identifying a type of said pressure sensor in accordance with a detected power source current value.

A pressure sensor system comprising:

a plurality of pressure sensors each having power source current values set therein as respective consumption currents which are different from each other, each of said pressure sensors comprising:
DC power source input terminals composed of two terminals;
a signal output terminal for outputting a signal corresponding to an applied pressure;
and
power source current-setting means for setting a power source current value flowing through said DC power source input terminals as a consumption current flowing through said pressure sensor, said power source current value being different depending on a type of said pressure sensor;
and
a pressure sensor control apparatus including type-identifying means to which said pressure sensors are connected, for detecting said power source current values to identify said type of said pressure sensor when a predetermined process is performed in accordance with an output of said pressure sensor.

4 more elements

Dependencies are inferred from the claim text.

Pressure sensor, pressure sensor control apparatus, and pressure sensor system

Life of this patent

Pressure sensor, pressure sensor control apparatus, and pressure sensor system

Life of this patent

Abstract

Claims13