The integration of high precision ADCs and DACs makes the ADuC702x series particularly suitable for medical applications such as an electrocardiogram (ECG), blood oximetry, or blood pressure monitoring.  This block diagram shows the ADuC7021 used in an ECG application for heart monitoring. The electrodes are connected to the patient with the signals from these filtered and fed to an instrumentation amplifier (AD620). The output of the instrumentation amplifier is then fed to the ADC input of the ADuC7021 while the DAC output of the ADuC7021 is used to control the input amplifier’s reference point. The patient readings are digitized on the ADuC7021 with the output data being sent to a master node or monitoring terminal via the UART interface.