2-cell Li-ion linear charger in a 3x3 DFN
The Microchip MCP73213-A6BI/MF is a dedicated linear charger IC for two-cell lithium-ion or lithium-polymer battery stacks, targeting an 8.4 V full-charge pack voltage. It delivers a constant current that you set with a single external resistor, up to a 1.1 A ceiling — no I2C, no firmware, just a resistor value to match your pack capacity. Built-in over-voltage fault protection means the part will shut down if the cell voltage drifts above the safe limit — a solid safety net if the regulation loop or the pass transistor fails short.
Charge current programming — one resistor, no software
The charge current is constant and programmable via an external resistor connected to the PROG pin — no digital interface, no configuration registers. This keeps the BOM simple and the firmware team out of the charging loop; the resistor value alone sets the current from a few tens of mA up to the 1.1 A maximum. For a typical 2000 mAh 2-cell pack, a 0.5 C rate (1 A) is a reasonable starting point, and the resistor tolerance directly sets the charge-current accuracy.
Package and thermal — the 3x3 DFN needs a via pattern
The MCP73213-A6BI/MF comes in a 10-VFDFN with an exposed pad, supplier device package 10-DFN (3x3 mm).