Texas Instruments rolled out a new battery charger IC that boosts the run time of compact consumer and medical electronics while cutting charging times and filling up more of the battery's available capacity. The new switching battery charger IC can add more than 5% of run time to the average battery crammed inside wearables, earbuds, patient monitoring devices and wireless charging cases, the Dallas, Texas-based company said.
The BQ25619 is designed to limit how much current is lost when the charge entering the battery is cut off—called the termination current. Once a lithium-ion battery is fully charged, energy must be shut down to prevent overcharging, which can not only degrade the battery's capacity but can also lead to dangerous conditions that cause it to overheat. It supports 20 mA in termination current. Other chips on the market draw more than 60 mA, Texas Instruments said.
The BQ25619 also limits standby current—also called the quiescent current—to 6 uA, doubling the battery's shelf life. The charger works with single-cell lithium-ion or lithium-polymer batteries, and it combines the buck charger and boost regulator into a single solution that can handle charging, discharging and voltage protection using a single inductor. That saves space for designers of consumer gadgets or medical electronics for uses like health monitoring.
The input currents supported by the 1.5-A battery charger IC range from 100 mA to 3.5 A while voltages range from 4V to 13.5V. The battery charger supports a wide range of input sources, including USB chargers, USB adapters and even wireless charging cases. Apple in March introduced its new wireless charging case for use with its popular AirPods earbuds. Samsung has also started selling a new wireless charging case for use with its Galaxy Buds earbuds.
The charger is slapped inside a 4mm by 4mm by 0.75mm WQFN package and boosts the average battery's run time by around 7% between recharges. Texas Instruments is targeting the new charger at designers trying to squeeze more run time out of ever-smaller batteries. The 24-pin BQ25619 is currently on sale for $1.45 each in 1,000-unit shipments. The company plans to roll out the 30-pin BQ25618 in a smaller WCSP package by the end of the current quarter.