Constant current (CC) sources and constant voltage (CV) sources are the two types of power sources to take into account while working with electronics.
The BQ24074 is a Li-Ion/li-poly linear charger with built-in power path management, which allows the device to power the system while charging the battery.
The MAX1898 is a highly advanced and efficient charging solution for 1-cell lithium-ion (Li+) batteries, when coupled with an external PNP or PMOS transistor.