ginngi engineering

A medical company needed an electronics module to interface to their proprietary sensor for measuring oxygen and CO2 levels in a patient's body. Since the instrument was portable and was consumer oriented, it needed to be low-cost and low-power. In addition, the external interface consisted of an IrDA, which is potentially power hungry, so an efficient design was necessary to minimize power.

The TI MSP430 microcontroller was chosen for its superior low power and low cost. The IrDA was chosen to provide the necessary isolation between patient and instrument grounds. The IrDA controller was chosen to easily interface to the microcontroller via its serial port and a control access protocol was designed to keep the IrDA transmitter off except for very brief times when data was to be transferred.