The maximum number of samples/second was 2380 Hz in serial cable transmission, whereas in microSD recording mode, a continuous ECG signal for up to 36 h at 500 Hz was verified. The fabricated device did not degrade the AD823X noise performance, and an ECG waveform with negligible distortion was obtained. Ultimately, a custom printed circuit board was produced requiring advanced manufacturing options of 2.5 mils trace widths for the small package components.

Simulation and testing assessed the system stability and performance parameters in terms of not losing any sample data throughout the length of the recording and finding the maximum sampling frequency and validation determined and resolved problems that arose in open-source development. A menu incorporates the device’s several operating modes. The data logging shield provides gigabytes of storage, as the signal is recorded to a microSD card adapter. The digitized ECG signal can be transmitted by serial cable, via Bluetooth to a PC, or to an Android smartphone system for visualization.

This required modifying the microchip with the breadboard-friendly Arduino Nano board in addition to a data logger and a Bluetooth breakout board. Starting with the evaluation board of the chip, open-source hardware and software components were integrated into a breadboard prototype. Relevant to mobile health, the design of a portable electrocardiograph (ECG) device using AD823X microchips as the analog front-end is presented.

Multisim footprint for an arduino nano