The following article presents a very simple low current 220 V mains operated transformerless power supply circuit using an inexpensive MJE13005 transistor and few other passive electronic components. As can be witnessed in the given circuit diagram, the design is extremely straightforward. How it Works Transistor T1, which is a high voltage NPN transistor MJE13005 forms the […]
Transformerless
Surge Protected Cheap Transformerless Hi-Watt LED Driver Circuit
The increased number of complaints from the readers regarding burning LEDs associated with my earlier posted transformerless 1 watt LED driver circuit, compelled me to solve the issue once for all. The power supply section of the circuit discussed here remains exactly identical to the previous configuration, except the inclusion of the “switch ON delay […]
High Current Transformerless Power Supply Circuit
The simple configuration of a transformerless power supply circuit presented below is able to provide high current at any assigned fixed voltage level. The idea seems to have solved the problem of deriving high current from capacitive power supplies which earlier seemed a difficult proposition. Introduction I have discussed a few transformerless power supply circuits […]
Transformerless UPS Circuit for Computers (CPU)
In this post I have explained how to build a simple UPS circuit for backing up computers or PCs during sudden power failures or brownouts. Introduction Normally when we talk about uninterruptible power supplies (UPS) we imagine large inverter units with complex features, where it imperatively needs to be a pure sine wave type. Such […]
Transformerless LED Bulb Circuits using Capacitors
In this post I have elaborately explained how to build simple transformerless LED bulb circuits using many LEDs in series and powering them through current controlled capacitive power supply circuit. Safety Note: These circuits operate directly from mains AC voltage without galvanic isolation, meaning live components carry high voltage when energized. Standard electrical safety practices […]
Transformerless Automatic Night Lamp Circuit
This transformerless solid-state automatic night lamp operates without using bulky transformer, and automatically switches ON some LEDs during night, and switches them OFF during day. In this post I have explained how to make a transformerless automatic darkness activated LED lamp circuit, using a couple of transistors and capacitive based power supply, eliminating the use […]