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FEATURES
GEN
INFO
A Atmospheric pressure,
intake air pressure
B Output voltage
C Input pressure
4
Vacuum chamber
5
Silicon chip
6
Pressure induction
pipe
1
Sensor unit
2
Hybrid IC
3
Silicon diaphragm
Intake air pressure sensor and atmospheric pressure sensor
S
Intake air pressure sensor
The intake air pressure sensor is used for measuring the intake air volume. The intake air volume of
every intake stroke is proportionate to the intake air pressure. Therefore, the intake air volume can
be measured by measuring the intake air pressure. The intake air pressure sensor converts the
measured intake air pressure into electrical signals and sends those signals to the ECU. When the
intake air pressure is introduced into the sensor unit, which contains a vacuum chamber on one side
of the silicon diaphragm, the silicon chip that is mounted on the silicon diaphragm converts the in-
take air pressure into electrical signals. Then, an integrated circuit (IC) amplifies and adjusts the
signals and makes temperature compensations, in order to generate electrical signals that are pro-
portionate to the pressure.
S
Atmospheric pressure sensor
The atmospheric pressure sensor is used for making compensations to the changes in the air densi-
ty caused by the changes in the atmospheric pressure (particularly at high altitudes). The operating
principle and function of the atmospheric pressure sensor are the same as those of the aforemen-
tioned intake air pressure sensor.