[FAQ] BQ25618: How does JEITA apply to the BQ25618, BQ25618E, BQ25619, BQ25611D, and BQ25616 as it relates to charge voltage and charge current?

The JEITA guideline was released on April 20, 2007 to improve the safety of charging Li-ion batteries. The BQ25618, BQ25618E, BQ25619, BQ25611D, and BQ25616 chargers have a TS pin, which is used with a thermistor and resistor divider in order to monitor the battery temperature. If the TS pin is outside of the T1-T5 range as specified in the datasheet, charging will be suspended until the TS voltage returns to within the T1-T5 range. Between T2-T3, full programmed charge current and charge voltage are applied. Please note in this FAQ that the BQ25618, BQ25618E, BQ25619, and BQ25611D will be referred to as “I2C Chargers.”

For all I2C Chargers, the charge current is configurable between T1-T2. The options for the charge current are 20% and 50% of the programmed charge current and is set by JEITA_ISET. For the BQ25616 the charge current is 20% of the programmed value between T1-T2. For both the I2C Chargers and the BQ25616 there is full charge current between T3-T5.

For all I2C Chargers, the charge voltage is configurable between T3-T5. The options for the charge voltage are 4.1 V charge voltage regulation or the programmed regulation voltage and is set by JEITA_VSET. For the BQ25616 the charge voltage is fixed at 4.1 V between T3-T5. For both the I2C Chargers and the BQ25616 there is full charge voltage between T1-T2.