SLUS987C January 2011 – December 2019 BQ33100
PRODUCTION DATA.
The BQ33100 measures the voltage on the capacitor stack when the LLEN pin (pin 17) is high with the initial learned value stored in Initial ESR, which is only updated once. The LLEN pin is controlled by firmware to enable a circuit that presents a constant current load to the full capacitor stack. With the known voltage and known current the ESR of the capacitor array can be determined. The final reported value of ESR is also adjusted by the data flash value of ESR Offset. The original value of the capacitor array ESR is stored in Design ESR but is not used by the BQ33100.
The final value of ESR can be read from the BQ33100 through ESR, which is in mΩ.