555 indication circuit of monitoring battery undervoltage condition

Published:2011/7/18 5:27:00 Author:nelly | Keyword: monitoring battery, undervoltage condition, indication circuit | From:SeekIC

As shown in the figure 10-25, undervoltage indication circuit is composed as the core of 555, when the monitoring voltage is undervoltage, it will send out alarm indication. In the figure, the circuit parameter is the monitoring voltage Vx=15v, when the battery voltage drops to 12V, LED1 turns on. 555's 5 foot is connected to 6V Zener diode, when the measured voltage drops, 2 foot's voltage VA≈Vx·R2/（R1+R2）=3.2v. When VA is lower than 3.2V, 555 is set, the output is high level, LED1 turns on, it shows that the battery should be charged or protected. For other monitored voltages(in the range of 5~15V), they also can be designed as this theory.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Signal_Processing/555_indication_circuit_of_monitoring_battery_undervoltage_condition.html

Print this Page | Comments | Reading(3)