Need help on what mehod to use....

[lantonyj]

Hello, I am somewhat familar with electronics but when it comes to putting everything together I'm not alll that great.

I want to have a circuit that has a supply voltage of 12v that will be regulated down to 5v using a 7805. The next voltage will be a linear 0v - 5v input that is oscilating depending on an external circuit. There will be 3 outputs which will go high based on the variable voltage. When the 0-5v which will be oscilating very quickly at times is between 0-1.23v output 1 will go high while 2 & 3 remain low, when it's between 1.24v - 1.32v output 2 will go high & outputs 1 & 3 are low & etc. The conditions of the outputs are variable, meaning some applications will require output 1 to go high between the range of 0-1.1v instead of 0-1.23v as mentioned before. Also the output high has to be above 4v.

Should I use comparators (window or not) with pots to adjust for the different input voltages. Which involves alot of adjusting...

Or a microprocess but I don't know the first thing about programming

Or could I use an eeprom?

Are eeproms generally used for something like this?

What would be the best way to acheive what I want that would be reliable?

Thanks for your time

 

[dknguyen]

Wse a microprocessor with an onboard ADC. LEss hardware to go wrong and if it does, you can just change the code. Less tuning involved too and more flexibility. THe logical responses you also want just make it needlessly complicated to discrete comparators and logic.

Not an EEPROM. THat just stores data.

 

[lantonyj]

WOW quick response, Thank you. To think I found many forums that I've asked questions in but no one would answer or they would be unnecessarily rude for asking. Anyhow, thank you.

The problem with using a microprocessor is that I don't know how to write the program. I found a rabbit 2000 chip & the development kit but again I don't know how to write C language. It wouldn't require much to get this down but I couldn't find any quick C tutorials.

Also what is an ADC? Analog to digital converter?

 

[Nigel Goodwin]

WOW quick response, Thank you. To think I found many forums that I've asked questions in but no one would answer or they would be unnecessarily rude for asking. Anyhow, thank you.

The problem with using a microprocessor is that I don't know how to write the program. I found a rabbit 2000 chip & the development kit but again I don't know how to write C language. It wouldn't require much to get this down but I couldn't find any quick C tutorials.

Also what is an ADC? Analog to digital converter?

Yes that's right, you can check my tutorials for PIC assembler help, it wouldn't take much writing in PIC assembler.

 

[lantonyj]

Again thank you for the replies.

Mr. Goodwin I have a question based off your reply...

How do you incorporate the two, microprocessor & ADC. Are the only parts needed a microprocessor the adc & a few resistors along with a voltage regulator?

During programming would I have 2 ports , one for programming the microprocess & the other for the adc. Or does the programming you suggest take care of both? Or is it once the microprocessor is programmed the ADC works from that...OK maybe not due to the microprocessor telling the ADC what to do & the ADC needs to know what to do with the information? With my setup I want the ability to change the circuit by plugging into the finished PCB - changing the trigger "values" for the 3 voltage outputs.

Sorry for the many questions, I'm in learning mode.

 

[lantonyj]

I just thought about this.... When you say microprocessor with ADC is this one unit? I've been looking based on information from here, are microcontroller chips that use PIC what I need? Are microcontroller chips such as an 8bit microcontroller a one stop shop deal?

 

[Nigel Goodwin]

I just thought about this.... When you say microprocessor with ADC is this one unit? I've been looking based on information from here, are microcontroller chips that use PIC what I need? Are microcontroller chips such as an 8bit microcontroller a one stop shop deal?

Many PIC's have in-built ADC's, mostly 10 bit ones, it makes projects VERY simple as far as hardware is concerned, and you just need to write the code - which with the PIC's RISC instruction set is fairly easy to learn.

 

[lantonyj]

Ok so if I understand everything correctly, my board would consist of a flash 10bit PIC which has an ADC, an 7805 (5v regulator), software & development kit such as DV164120 - PICkit 2 Starter Kit from microchip ( who seems to be the only large PIC provider), a socket for the PIC & a connection to allow programming of the PIC on the PCB?. Are the PICs programmed before installing on the PCB or can they also be programmed while in the PCB?

Also, if any what are the draw backs of using PICs.

Thank you very much for your help, I went to your site which is very helpful.