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RT9428
Host-Side Single Cell Lithium Battery Gauge
General Description
The RT9428 is a compact, host-side fuel gauge IC for lithium-ion (Li+) battery-powered systems.
For the embedded Fuel Gauge function, the state-ofcharge (SOC) calculation is based on the battery voltage information and the dynamic difference between battery voltage and relaxed OCV, by using iteration to estimate the increasing or decreasing SOC.
Voltage-based algorithm can support smoothly SOC and does not accumulate error with time and current. That is an advantage compared to coulomb counter which suffer from SOC drift caused by current-sense error and battery self-discharge. The disadvantage of voltage-based fuel gauge, it can report incremental SOC (%), but can't report capacity (mAh).