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View Full Version : Which pic should I buy now?



atwoz
- 9th December 2007, 06:47
Hello! I have worked with some pics: 12f508, 16f84, 16f628, 16f88, 16f877, 16f887, 18F452.

I know these some of the most famous around, I was wondering if someone could recommend to me some other pic, with nice features. Price is not important. Thanks!

WoZ

Darrel Taylor
- 9th December 2007, 07:31
Hi WOZ,

That's a pretty good sampling you've done so far.
By now you should have a good idea of the kinds of features that are available in the different chips.

But I think it's time to take it to the next step. ...
Choosing the chip according to what you need it to do.

Which is the first question ...

What do you want to try next?
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atwoz
- 11th December 2007, 08:48
Thanks for the response Darrel, I have some ideas that involve batteries. You know, 3v instead of 5v. Also, I'm not sure if that exists but a pic that consumes very little power would be great.
Are there ways to make your pic consume less power? I remember reading somewhere that making your pic's clock slower consumes less power, is that true?

Jumper
- 11th December 2007, 10:07
On Microchip's webpage under 8-bit PIC microcontrollers you can find nanoWatt technology. They all require very little power to run. And then it is just a matter of money and size to find which one is best for you.

USB - no USB, more or less program space, RAM??? If you really want to save power you should pick a PIC that has a built in oscillator that is a as slow as possible, usually 32 kHz.

So a 18F4550 (with usb support for later new ideas) running on 2V will be needing a few uA. But then if you can put it to sleep for most of the time we are talking about around 0.1 uA. Slower saves power, and sleeping saves most.

But there are many many many, both 16-series and 18-series that will do a great job.

/me

atwoz
- 12th December 2007, 05:28
Thanks a lot Darrel I will look into that nanowatt tech, I believe the 16f88 has that doesn't it?

One more thing, you mean running a pic with only 2V as a supply? That would be awesome, does any of the pics I mentioned again can run like that?

Jumper
- 12th December 2007, 07:45
Hi,

A quick look at the microchip webpage, under nanoWatt technology will give several PICs that can run from 2V to 5.5V. 16F88 is one of them (and the datasheet will tell you even more). Just scroll the list to the right and you will see the operating voltage. Most (All?)nanoWatt pics can run on 2V.

/me

mackrackit
- 12th December 2007, 07:59
Look at the data sheet under "Electrical Characteristics" or Specifications.

On the chips that run on lower voltages the clock speed has to be slowed down.

At 8 MHz the 16F684 will run at 2 volts.
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