Summary: How to design, prototype and test a two cell 18650 Lithium Ion battery pack level gauge using the classic LM3914 dot/bargraph display driver chip. A favorite from Dave’s youth! Dave gives you all you need to know to implement a simple expanded scale voltmeter with the LM3914, without adjustment pots to tweak. This one works from 6V to 8.4V – the usable capacity of a two 2 cell 4.2V Li-Ion batttery pack.
