Mains Voltage monitor using LM3914
This Circuit helps in the monitoring of mains supply voltage. It does not use a isolation step down transformer. This has to be constructed only by skilled people with knowledge of safety requirements. C1...
Category: LED-Circuits
Constant Current Source LED Drive
This is a Constant Current Source LED Driver, When the LED driver Upper-NPN is driven by a voltage thru 4.7K the LED lights up. Assume that the Lower-NPN at bottom is absent. The current...
Battery Level LED Indicator
This LED Indicator uses a LM339, a quad comparator. LM339 can work on single or dual supplies, it has a open collector output that can drive 15mA, low power consumption. The circuit is an...
Simple Mains Voltage monitor
This Circuit helps in the monitoring of mains supply voltage. It does not use a isolation step down transformer. This has to be constructed only by skilled people with knowledge of safety requirements. C1...
