What this ECG front-end does on the board
The MAX30003CWV+T is a single-channel ECG front-end IC, purpose-built for extracting the P-Q-R-S-T complex from a chest-strap or patch electrode pair. It integrates the instrumentation amplifier, right-leg drive, and baseline-wander rejection — the analog chain that turns a few microvolts of differential skin potential into a digital stream the host MCU can process.
Supplied in a 30-bump WLP (2.74 x 2.93 mm) — a wafer-level chip-scale package that places the die bumps directly on the PCB pads, so the stencil aperture and reflow profile must match the 0.4 mm pitch typical of this class. Surface-mount only; the 30-WFBGA footprint demands a clean solder-paste deposit and a nitrogen reflow environment to avoid head-in-pillow defects on the small bumps.
ROHS3 compliant; the part carries no restricted substances above the threshold, which simplifies the EU declaration of conformity for a medical-device BOM.