SLUUBD4A April 2016 – November 2022 BQ27220
Upon power-up or pack insertion, an open-circuit voltage (OCV) measurement of the battery is made via the BAT pin. For best gauging results, the system load during the OCV measurement should not exceed a C/20 discharge rate of the battery. For this first critical measurement, both BAT_GD and SOC_INT pins are available for system synchronization. (See Section 5.2.4, Power Path Control With the BAT_GD Pin, Section 5.2.3, SOC_INT Pin Behavior, and Section 3.2.8, OCV_CMD: 0x000C.)
Upon completion of the OCV voltage measurement, the BatteryStatus()[OCVCOMP] is set.