Blood Pressure Monitor
Figure 5. Blood pressure monitor general block diagram
5 Blood Pressure Monitor
This section explains the hardware background to develop a blood pressure monitor. The functionality of the MPXV5050GP
pressure sensor, the hardware, and software developed are also described.
5.1 Pressure Sensor
This application implements the motor control mentioned in the
driven by a pulse width modulation (PWM). The
principal device for this application is the MPXV5050GP pressure sensor. This is because it depends on the pressure detected
by the MCU so that the motor either turns on or turns off. Also important is an air compressor controlled by the motor and valve.
The pressure sensor provides a signal that splits in two. One without a filter, and the other with a filter that removes noise.
MPXV5050GP medical features:
• Patented silicon shear stress strain gauge
• Pressure range up to 300 mm Hg (consult the datasheet)
• Polysulfone case material (medical, class V approved)
5.2 Hardware—Blood Pressure Monitor
The motor must be connected to the mini air pump valve to generate air for the air chamber, at the same time, the mini air pump
has to be connected to a cuff, an air reference, and to the valve. Therefore when the motor is disabled and the valve enabled,
the cuff starts to deflate. The pressure sensor is also connected to the cuff for taking in every moment and measuring the pressure.
shows how to connect these elements. A hose can be used.
Implementing a Glucometer and Blood Pressure Monitor Medical Devices, Rev. 1, 4/2010
Freescale Semiconductor, Inc.
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FREESCALE [ FREESCALE SEMICONDUCTOR, INC ]
