• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Please help me RECTIFY this problem :)

Status
Not open for further replies.

subzero349

New Member
Hello all,

I need detect the zero crossings of a 120V ac signal and act on it.

So far I have a transformer that converts the 120V to 12V (500mA).
I have the signal going into a rectifier (4 4001 diodes in a diamond shape - I think it's called a full wave rectifier...

anyway... the output is full wave recified... is there any circuitry anyone can suggest to turn this into a nice square wave where it goes high/low on a zero cross?

will a schmitt or something? or an H11L1?
 

subzero349

New Member
(I also replied in the general section)

thank you ron, I do have an alternate source for dc, can you please post the simpler circuits? :)

basically I want to do 2 things:

1. use the 555 to control the intensity of a 120V ac light bulb (or small motor)

2. use a PIC microcontroller to control the intensity of the same thing...

I want to start with the 555 and than move on to using a microcontroller instead...
I have a question: do you need to detect the zero crossings and make sure the pulses start on the zero crossings? Can you clarify exactly what a triac is actually doing??

Any help would be greatly appreciated
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top