VA7204L2中文资料Advanced Linear Charger IC for A Single Lithium-ion Battery数据手册Vimicro规格书

描述 Description

VA7204L2 is a single cell Lithium-Ion (Li-Ion) linear charger IC designed for cost-sensitive and compact portable electronics. It combines high-accuracy current, voltage regulation, battery condition monitoring, thermal regulation, charge termination, and charge status indication in a single 6-pin IC.

VA7204L2 monitors the battery charging status by detecting the batter voltage. VA7204L2 charges the battery in three phases: preconditioning, constant current and constant voltage. If the battery voltage is below the low-voltage threshold VMIN (normally at 3V), VA7204L2 precharges the battery using a low current. The conditioning charge current can be adjusted with an external resistor. When the battery voltage reaches VMIN, VA7204L2 applies a constant current to charge the battery. An external sense resistor controls the current. The constant current charging continues until the battery voltage reaches the charge regulation voltage (normally at 4.2V). And then VA7204L2 enters the constant voltage charging phase. The accuracy of the voltage regulation is better than ±1% over the operating temperature and supply voltage range. Under the condition, the charging current gradually decreases. Charge stops when the current tapers to the charge termination threshold, ITERM. VA7204L2 monitors the battery voltage continuously and enters a new cycle of charging if the battery’s voltage falls below VRECHG (normally at VREG - 150mV). \r