2-3
2.3 Main Unit
The pulse oximeter consists of main board, SpO
2
board, display, speaker, batteries and
charger stand. The main board is composed of a main control unit and a power module.
The following diagram shows the structure of the main unit.
2.3.1 Main Control Unit
The main control unit provides the system with resources and support. It controls the LCD
screen, alarm LED, speaker, button operation and data storage. It also implements
communication with the SpO
2
board, power module and external interfaces.
The functional block diagram of the main control unit is shown below: