TI BQ24650RVAR

The BQ24650 device is a highly integrated switching-mode battery charge controller. It provides input voltage regulation, which can reduce the charging current when the input voltage is lower than the programmed level. When a solar panel is used to power the input, the input regulation loop reduces the charging current to enable the solar panel to provide maximum power output. The BQ24650 provides a constant-frequency synchronous PWM controller with high-precision charging current and voltage regulation, pre-charge regulation, charge termination, and charge status monitoring functions. The BQ24650 charges the battery in three stages: pre-charge, constant-current charge, and constant-voltage charge. The charging operation is terminated when the current reaches 10% of the fast-charge rate. The pre-charge timer is fixed at 30 minutes. The BQ24650 automatically restarts the charging cycle when the battery voltage is below the internal threshold and enters a low quiescent current sleep mode when the input voltage is below the battery voltage. The BQ24650 supports a battery voltage range from 2.1V to 26V, and the VFB is set to a 2.1V feedback reference. The charging current can be programmed by selecting an appropriate sense resistor. The BQ24650 comes in a 16-pin, 3.5mm×3.5mm² thin QFN package.

• Maximum Power Point Tracking (MPPT) via input voltage regulation
• Programmable MPPT settings
• 5V to 28V input solar panel
• 600kHz NMOS-NMOS synchronous buck controller
• Resistor-programmable float voltage
• Compatible with Li-Ion/Polymer, LiFePO₄, and lead-acid battery chemistries
• Accuracy – ±0.5% charge voltage regulation, ±3% charge current regulation, ±0.6% input voltage regulation
• High integration – internal loop compensation, internal digital soft-start
• Protection – input overvoltage protection, battery temperature sensing, battery undervoltage detection, thermal shutdown
• Charge status output for LED or host processor
• MPPSET charge enable pin
• Automatic sleep mode for reduced power consumption – shutdown battery discharge current <15μA
• Compact 3.5×3.5mm², 16-pin QFN package

• Solar-powered applications
• Remote monitoring stations
• Portable handheld instruments
• 12V to 24V automotive systems
• Current-limited power supplies