Single-cell Li-Ion/Polymer linear charge controller — 4.2V termination at 450mA
The MCP73811T-420I/OT: This is a constant-current linear charge controller for single-cell Lithium Ion or Lithium Polymer batteries. It terminates at 4.2V and delivers up to 450mA charge current. The linear topology means no switching noise — a clean charging profile for noise-sensitive portable devices like wearables, IoT sensors, and handheld instruments. Maximum supply voltage is 6V, so the part runs directly from a standard 5V USB bus or a regulated 5V rail without an external LDO ahead of it.
SOT-23-5 package — small footprint for space-constrained boards
Surface-mount with a 5-pin footprint — the board area is minimal, making it a natural fit for compact single-cell battery designs where every mm² counts.
ROHS3 compliance and packaging options
The part is ROHS3 compliant, which satisfies EU RoHS Directive 2011/65/EU and its amendment 2015/863 — no exemption-based paperwork needed for European BOMs. The reel option suits production pick-and-place; cut tape works for prototype quantities without committing to a full reel.