BQ2002PNG4

PMIC - Battery Chargers are applied to devices that require continuous energy for everyday operations, such as phones, laptops, and tablets. The BQ2002PNG4 is an integrated Battery Charger from Texas Instruments, specially designed for single-cell Li-Ion and Li-Pol rechargeable battery applications. It is equipped with a wide range of charging algorithms for charging different battery types with various modes and states. The device can detect battery presence, control the charging current and select various charging states based on the input supplied to its digital inputs, as well as its internal thermistor reading.

BQ2002PNG4’s working principle is simple. It enforces a step-by-step process to ensure that the battery is charged efficiently and safely. The user must first provide the necessary inputs, such as the type of battery and the desired charging current, to the BQ2002PNG4’s digital inputs. The device will then use the two protected inputs C3 and C4 to detect battery presence. Upon detecting a battery, the BQ2002PNG4 will set its internal registers (an input/output mapping) to correspond to the selected battery profile and charging algorithm. This information is sent to its power stage, which enables the charging current from the VDD and VBAT supply pins. After this, the BQ2002PNG4 reads its temperature sensor and adjusts the current and voltage accordingly. The device has four dedicated charge states: Pre-charge, Constant-current, Constant-voltage, and Termination.

The Pre-charge stage helps the BQ2002PNG4 to protect the battery from potential damage due to rapid charging. The device achieves this by supplying a much lower charging current and voltage to the battery and slowly ramping them up after battery presence is detected. The Constant-current step is when the BQ2002PNG4 delivers a constant current to the battery, allowing for a relatively quick battery recharge. The Constant-voltage step is when the BQ2002PNG4 switches from a constant current to a constant voltage supply to the battery, allowing for a gradual ramping up of the battery voltage. Finally, in the Termination stage, the BQ2002PNG4 detects when the battery is fully charged and shuts off the power stage, ceasing the recharge process.

The BQ2002PNG4 also has many other features that ensure safe and efficient charging of single-cell Li-Ion and Li-Pol batteries. The device is able to detect if an incorrect battery has been inputted to its digital inputs and will provide an alarm in such cases, increasing system safety. The device comes with reverse current and auto-restart protection against unusable battery conditions. On top of this, it also provides temperature sensing, current sensing, and voltage sensing features, allowing for real-time monitoring of battery charging and protection against undesired conditions.

In conclusion, the BQ2002PNG4 is a highly efficient and reliable battery charging device, ideal for integrated systems that require a continuous energy source for everyday operations. Its charging algorithm and various charge states allow for quick and safe charging of different single-cell Li-Ion and Li-Pol rechargeable batteries, while its various features provide protection against undesired conditions, making the device a perfect choice for battery charging applications.