Technology and Medical Devices
Figure 11. Oscillatory pressure curve
5.6.3 Mean Arterial Pressure
Mean arterial pressure (MAP) is a term used in medicine to describe an average blood pressure in an individual. It is defined
as the average arterial pressure during a single cardiac cycle.
At normal resting heart rates the MAP can be approximated using the more easily measured systolic pressure (SP) and diastolic
pressures (DP):
6 Technology and Medical Devices
Medical diagnostics are now made with high technology avoiding continuous visits to the hospital. Making remote control
LCDs can be used as an interface to communicate with the patient at different stages of the disease and generate alarms in
chronic situations. The application also has different ways to communicate with external devices such as Bluetooth, SD Card,
and USB.
7 LCD Driver
This application was developed using the MC9S08LL16 series. This device provides an LCD module that controls up to 192
segments and generates the waveforms necessary to drive an LCD. The LCD used for this application is a glass with 29 segments.
7.1 Modes of Operation and Power Supply
In the MC9S08LL16 series the LCD module can be configured to operate in Stop and Wait modes. The LCD module can operate
in stop2 with all clocks turned off.
According to the LCD glass specifications this must be supplied at 3.3 V. For this configuration VIREG is connected to VLL1
internally and a range of 1V for the VIREG is chosen. VLL2 and VLL3 are generated by a charge pump. Figure 12 shows the
connections between the LCD glass and the MCU.
Implementing a Glucometer and Blood Pressure Monitor Medical Devices, Rev. 1, 4/2010
Freescale Semiconductor, Inc.
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FREESCALE [ Freescale ]
