1 - 9
Theory of Operation
Main Unit
The CPU generates analog signals by controlling the DAC chip on the power management
and interface board via the I2C bus. The analog signals are transmitted to the BNC socket
via the amplifier circuit.
FIGURE 1-8
The amplifier circuit
The signal r_flag from the multi-parameter board goes to the power management and
interface board. The CPU can select the source of defibrillator synchronization signals by
controlling the output of the DAC. The signal r_flag also goes to the CPU for a self-test.
Two UART interfaces (serial port 1 and serial port 2) from the CPU board are extended as
two RS232-level ports via the power management and interface board. Both interfaces can
be configured to accommodate a PC for data or an AG module.
FIGURE 1-9
The serial ports
