AC Dimmer

[leaveme]

Hi,

I'm looking for an AC dimmer. I checked in code library but couldn't find anything.
Anybody has a working dimmer in CCS?
Do you mind to share...pls.

Thanks.

[asmboy]

did you search on the term:

[leaveme]

I tried the search but didn't return anything good.

[asmboy]

you asked this same question recently - and got other info.

what is your approach to solving this?

or more simply - how do you plan to go about

creating the circuitry and code to do it?

if you have no clue of where or how to start - THEN-
might i suggest the "100 series" courses in
electronics and engineering, at any local higher educational institution
as being a very good start.

I believe that is the way that most of us here learned to do electronic design ourselves.

[temtronic]

Microchip has several application notes about using PICs for AC dimmer control.While most are in Assembler(easy to learn) it is easy enough to translate into CCS C code.
All it takes is some reading and code cutting.

As well try 'googling' and you should come up with a few thousand 'hits'. Again, while some will be in another version of PIC C, easy to translate.

[leaveme]

Thanks guys.

I tried google as well and google returned tons of references. But they are mostly assembler. Unfortunately I can't read asm.

I asked here if anyone willing to share a dimmer...anything in CCS. That will be a reference point for me.

[asmboy]

As a starting point -

Do you have a schematic of how you plan to do the
actual AC control?

Using a triac or other modulator?


What POWER level in, say watts, that you want to control?

Your line volts and frequency??

Whether or not you will need to run at very low duty cycles - ie
below 10% "ON" ?
which leads to....

A circuit to tell the pic when the mains power zero cross occurs,
with good enuf stability not to flicker at low modulation settings?

HOW you plan to tell the PIC what amount dimming you wish ?
{
Read a POT ??
listen to RS-232 ??
smoke signals ??
} //

The FIRST step in any design - is to, well, set the design specs right??

[leaveme]

Hi asmboy,

I just need a simple dimmer in PIC, i.e. a dimmer by which you can control a 100w 220v/50Hz AC lamp.

Duty cycle is about 25% to full and a POT can be used to control.

I have no idea for zero cross synchronization. Any reference or example will really help.

Thank you.

[Ttelmah]

Seriously, the words 'sledgehammer', and 'egg' seem to apply here.

Problem is that to use a PIC, means adding a power supply to run the PIC. PIC+PSU+dimmer, equals perhaps 10* the number of components needed for a simple dimmer.
Have a look at:
<http://www.aaroncake.net/circuits/dimmer.asp>
or any one of the dozens of similar circuits online.

Dirty, likely to make quite a lot of RF noise, and you _must_ ensure that you use a potentiometer that has a safe AC insulation rating, but shows just how simple a dimmer can be.

Where a processor does 'come in', is if (for instance) you want the circuit controlled from another location, or need to reduce RF (this is where zero-crossing comes in), but all involve increasing complexity.

Unless you need the extra features, KISS

Best Wishes

[leaveme]

Thanks Ttelmah.

I need something MCU controlled so complexity is ok with me.
Aah...nobody made similar yet...

[RF_Developer]

[ckielstra]