Inverter circuit diagram using 555
Your project is to design and build a power inverter to convert 12 volts DC to 120 volts AC. A suggested
circuit is shown here
Please note that this is only a general schematic, and may not be exactly what you need to build in order to have a successful inverter circuit. Your choice of specific power components (transformer, power MOSFETs, zener diodes) are critical. Paralleled MOSFETs and zener diodes may very well be in order!
Deadlines (set by instructor) :
• Project design completed
• Components purchased
• Working prototype
• Finished system
A common topology for DC-AC power converter circuits uses a pair of transistors to switch DC current through the center-tapped winding of a step-up transformer
In order for this form of circuit to function properly, the transistor “firing” signals must be precisely
synchronized to ensure the two are never turned on simultaneously. The following schematic diagram shows
a circuit to generate the necessary signals
Explain how this circuit works, and identify the locations of the frequency control and pulse duty-cycle
The zener diodes shown in the schematic are there to absorb transient voltages resulting when the
MOSFETs turn of. Explain where these transients originate from, and what might happen if the zener
diodes were not there.
Examine these checkplot images from a PCB drafting program, for a control board based on this inverter circuit design. Both the top and bottom copper layer plots are shown from the perspective of the board’s top side. The six large “pads” around the periphery of the board are actually holes for mounting screws
Mark where discrete components (resistors, capacitors, and diodes) go into the PCB, and identify which integrated circuits on the board layout are performing which functions in the schematic. Note: the square pad on each IC marks pin number 1
suppose you were prototyping this circuit without the benefit of an oscilloscope.
How could you test the circuit to ensure the final output pulses to the transistors are never simultaneously
in the “high” logic state? Assume you had a parts assortment complete with light-emitting diodes and other