link to page 1 50 µA, 2 mm × 1.7 mm WLCSP, Low Noise,Heart Rate Monitor for Wearable ProductsData SheetAD8233FEATURESFUNCTIONAL BLOCK DIAGRAMFully integrated, single-lead ECG front endA4B4A3A2A1HPSENSEIAOUTREFIN+VLow quiescent supply current: 50 µA (typical)SGNDHPDRIVELeads on/off detection while in shutdown (<1 µA)A5FRB3S1 10kΩA3Common-mode rejection ratio: 80 dB (dc to 60 Hz)+IN2-electrode and 3-electrode configurationsB5AC/DCB2–INIAHigh signal gain (G = 100) with dc blocking capabilitiesC52-pole adjustable high-pass filterSDN150kΩB1Accepts up to ±300 mV of half cell potentialAD8233C4Fast restore feature improves filter settlingRLDFBUncommitted op ampRLD SDNC2D5A23-pole adjustable low-pass filter with adjustable gainRLDLODLEADS OFFIntegrated RLD amplifier with shutdownDETECTIONCC1Single-supply operation: 1.7 V to 3.5 VS2Integrated reference buffer generates virtual ground10kΩA1Rail-to-rail output 001 SWOPAMP+REFOUTOPAMP–OUTD4D3C3D2D1Internal RFI filter 13737- 8 kV HBM ESD rating Figure 1. 20-Ball WLCSP Shutdown pin To improve the common-mode rejection of the line frequencies 2 mm × 1.7 mm WLCSP package in the system and other undesired interferences, the AD8233 APPLICATIONS includes a right leg drive (RLD) amplifier for driven electrode applications. Fitness and activity heart rate monitors The AD8233 includes a fast restore function that reduces the Portable ECG duration of the otherwise long settling tails of the high-pass Wearable and remote health monitors filters. After an abrupt signal change that rails the amplifier Gaming peripherals (such as a leads off condition), the AD8233 automatically adjusts Biopotential signal acquisition, such as EMG or EEG to a higher filter cutoff. This feature al ows the AD8233 to GENERAL DESCRIPTION recover quickly, and therefore, to take valid measurements The AD8233 is an integrated signal conditioning block for soon after connecting the electrodes to the subject. electrocardiogram (ECG) and other biopotential measurement The AD8233 is available in a 2 mm × 1.7 mm, 20-ball WLCSP applications. It is designed to extract, amplify, and filter small package and a 150 μm thin die for height constrained applications. biopotential signals in the presence of noisy conditions, such as Performance is specified from 0°C to 70°C and is operational those created by motion or remote electrode placement. This from −40°C to +85°C. design allows an ultralow power analog-to-digital converter The AD8233 has several improvements over the AD8232, (ADC) or an embedded microcontrol er to easily acquire the which are detailed in Table 1. output signal. Table 1. AD8232 vs. AD8233 Comparison The AD8233 implements a two-pole, high-pass filter for ParameterAD8232AD8233 eliminating motion artifacts and the electrode half cel potential.
