Battery internal resistance is determined by repetitively stepping calibrated discharge current and reading resultant voltage drop. S1-based modulator, clocked from frequency divider, combines with A1-Q1 switched current sink to generate stepped, 1 ampere
Figure 2. Battery internal resistance is determined by repetitively stepping calibrated discharge current and reading resultant voltage drop. S1-based modulator, clocked from frequency divider, combines with A1-Q1 switched current sink to generate stepped, 1 ampere