An ECG data acquisition device (10) can be mechanically engaged with a portable device (20) to form a combined unit. The ECG data acquisition device (10) includes a housing (11), at least two electrodes located on the surface of the housing (11) for obtaining ECG signals from a user, and a circuit assembly (100). The circuit assembly (100) includes an analog signal processing module (102), a processing module (104) having an analog/digital converter (1041), and a processor (1042) to execute a preloaded program to perform the ECG acquisition and data processing, and a communication module (106) for communicating with the portable device (20).
