The PCA9420UKZ: Input supply range is 3.3 V to 5.5 V — this covers single-cell Li-ion (3.6-4.2 V), 3.3 V regulated rails, and 5 V USB VBUS. The part does not require a pre-regulator for any of these common sources, which simplifies the front-end BOM. This suits outdoor IoT nodes, automotive cabin electronics, and industrial sensor modules that see ambient heat but not engine-bay extremes.
WLCSP footprint and board-fit constraints
Housed in a 25-bump WLCSP, 2.09 x 2.09 mm. The 0.4 mm pitch typical of this class demands a controlled solder-paste stencil and a reflow profile matched to the board thickness — the package itself is the floorplan reference for the decoupling capacitor placement. Surface-mount only; the WLCSP has no exposed paddle, so thermal management relies on the PCB copper plane under the die. A four-layer board with a solid ground plane beneath the package is the standard thermal strategy.
Tape & Reel logistics for the procurement desk
Cut Tape works for prototype or low-quantity BOM fills.