This circuit was found in the April 1984 issue of Radio Electronics magazine. The integrated circuit used is a type of time that already includes the power supply.
Based on a 555, this 80's American documentation circuit detects the voltage of a battery and can then...
In the figure we have the use of one of the four existing amplifiers in the LM2900 and LM3900 as a...
12 V battery chargers provide higher unregulated voltage. With the regulator shown, obtained from...