In this post I have explained an enhanced transformerles power supply circuit design which consists a well stabilized and regulated DC stage along with a relay driver stage which operates through an external pulse. he idea was suggested by Mr. Reza. Technical Specifications Reza: Dear Sir, I have a problem with one Circuit regarding converting […]
Transformerless
0-300V Adjustable Transformerless Power Supply Circuit Diagram
This simple MOSFET controlled transformerless power supply circuit can be used for delivering a continuously variable 0 to 300V DC output and a current control from 100 mA to 1 Amp. To protect against my high voltage research projects from going up in smoke permanently, I developed an easy circuit which is able to render […]
Transformerless Power Supply Circuit using MJE13005
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 […]
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 […]





