Very simple low battery indicator schematic is based on two transistors . The led connected in this circuit will flash when the voltage is low ( bellow 5 volts ) . The circuit consumption is very low ( about 25 micro amps ) when the led is not flashing .
The L200 regulator is a monolithic integrated circuit can be used in power supply with voltage and current programmable regulation .This L200 regulator power supply regulation schematic can replace fixed voltage regulators when is required high output voltage precision .
Main features of L200 regulator are : adjustable output current up to 2 ampers , input voltage protection up to 60 V , short circuit protection , thermal overload protection .
The L200 circuit can be used in many other applications like motor controller , lamp controller , battery charger .
The ICL8211/8212 are micropower bipolar monolithic integrated circuits intended primarily for precise voltage detection and generation. These circuits consist of an accurate voltage reference, a comparator and a pair of output buffer/drivers.
Specifically, the ICL8211 provides a 7mA current limited output sink when the voltage applied to the ‘THRESHOLD’ terminal is less than 1.15V (the internal reference).