Battery-Switching Circuit for Dual-Battery Systems
Original Publication Date: 1989-May-01
Included in the Prior Art Database: 2005-Jan-28
This article describes a circuit arrangement which provides a means of detecting a low-battery condition on a dual-battery system, disabling the main battery and drawing power exclusively from the backup battery until a recharger is connected to the main battery. The circuit disclosed herein allows a system that utilizes two batteries (main and backup) as its power source to detect a low-battery condition on the main battery and instruct the system to disable the main battery and draw its power exclusively from the backup battery when the low-battery condition occurs and remain in this state until a recharger is connected to the system. The circuit, as shown in the drawing, utilizes linear, CMOS and discrete components that are readily available.