Cxlb7276 is a circuit specially designed for high precision linear lithium battery chargers, which is very suitable for those low-cost, portable chargers. It can be widely used in EPC, mobile multimedia, handheld devices and other fields.
Cxlb7276 determines its charging state by detecting the battery voltage: pre charging, constant current charging, constant voltage charging. When the battery voltage is less than the threshold voltage Vmin (generally 6V), it is in the state of precharge. The battery is charged with a small current. The current of precharge can be adjusted by external resistance. After the pre charging makes the battery voltage reach Vmin, it enters the fast charging state of constant current charging. The charging current ireg can be adjusted by the peripheral resistance R1. The constant current charging makes the battery voltage rise to the constant voltage charging voltage vreg (generally 8.4v). Then enter the state of constant voltage charging, the accuracy of charging voltage is better than ?1%, in this state, the charging current will gradually reduce, when the charging current is less than the threshold iterm, the charging is over. After charging, the battery voltage will always be monitored. When the battery voltage is less than the threshold vrechg (generally vreg-250mv), the battery will be recharged to enter the next charging cycle.