METHOD AND DEVICE FOR MEASURING CHARGING CURRENT AND DISCHARGING CURRENT OF STORAGE BATTERY USING DIRECT ANALOG-TO-DIGITAL CONVERSION OF CHARGING REPLICA CURRENT /DISCHARGING REPLICA CURRENT

摘要

PROBLEM TO BE SOLVED: To realize value for charging/discharging current in a digital form by a direct analog/digital conversion function, in a storage battery energy management circuit. SOLUTION: A storage battery charging current Icharge for charging a storage battery is generated at a first node 2, and a replica current Irep is generated from the current Icharge at a second node 10 (where Irep<; Icharge) for actuating a closed-loop current consumption part for absorbing the current Irep. The digital output from the consumption part is a measure of the size of the current Icharge. The digital output is an input to a control circuit for controlling generation of the current Icharge. The consumption part comprises a multi-stage DAC, driven by an output from a digital filter of n levels which are increased/decreased as a function of the difference in voltage between the first node and the second node.