Shown here is the summary of the differences between the ISL9237 and ISL9238: ISL9238 supports up to 4-cell battery, has full range OTG, and is capable of handling larger VDD over current (OC) threshold to drive larger gate capacitance MOSFETs which results in better efficiency. Both parts are pin-to-pin, while the ISL9238 provides an additional feature for autonomous charging and end of charge. Renesas also created another part number, the ISL9238A, in case a design needs 2 chargers but there are not enough I²C addresses from the USB PD controller.