应用笔记 4840

Battery/Charger Load Switch Approximates Ideal Diode

By: Budge Ing

摘要 : Two circuits are described. The first uses external MOSFETs driven by the Power OK (POK) output of a Li-cell charger IC (MAX8814), to switch a load between battery and charging source without intervention from a microcontroller or system software. For charger ICs without a POK output (such as the MAX1507), the second circuit does the same switching using MOSFETs and a comparator (MAX920).