800-mA linear charger for 1-cell to 4-cell supercapacitor

The BQ25173 is an

integrated 800-mA linear charger for 1- to 4-cell supercapacitors targeted at

space-limited applications. The device has a single power output that charges

the supercapacitor. The system load can be placed in parallel with the

supercapacitor; the charge current is shared between the system and

supercapacitor.

During charging, an

internal control loop monitors the IC junction temperature and reduces the charge

current if the internal temperature threshold, TREG, is exceeded. This

feature allows for fast charging of a fully discharged supercapacitor.

The charger power

stage and charge current sense functions are fully integrated. The charger function

has high accuracy current and voltage regulation loops, charge status display, and

charge function control. The charge voltage and fast-charge current are programmable

through external resistors.