8pin voltage convertor

Hi,
Can anyone suggest an 8 pin flash chip that can take an analog voltage between, say 0 - 1 volts and out put a proportionally higher analog voltage, based on the math I will do in the code. I also want it to run on internal oscillator to minimize parts count.
I haven't designed anything in a long time and have forgotten most of the chip numbers and their functions information. Also don't need any more than one pin input and one pin out.
Thanks for the help!
Ron

What about using an op amp?

An op amp will do it. But consider the fact that, unless you have a negative voltage power supply available (so that the op-amp is powered by + and - voltages), you can't amplify a voltage very near "0". If you can tolerate a little non-linearity near 0V, and you only have a positive supply available (say +5V), you can use a rail-to-rail input/rail-to-rail output type. A good place to look is -

http://www.national.com/cat/index.cgi?i=i//11

Good point Charles.

I have been using a LM358 for thermo couplers.
single supply: 3V to 32V
dual supplies: ±1.5V to ±16V

Could you use a 12F683, vary the duty cycle of the PWM output according to the input voltage, and smooth it?

For the op-amp approach, you might see if the TLC271 would work well enough in a single-ended application.

Quote:

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Originally Posted by MARAD75

Hi,
Can anyone suggest an 8 pin flash chip that can take an analog voltage between, say 0 - 1 volts and out put a proportionally higher analog voltage, based on the math I will do in the code. I also want it to run on internal oscillator to minimize parts count.
I haven't designed anything in a long time and have forgotten most of the chip numbers and their functions information. Also don't need any more than one pin input and one pin out.
Thanks for the help!
Ron

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Any pic with ad a/d and pwm can do it. Use an external 1v reference (or slightly higher for protection), and a voltage divider to scale it down where you want, and then you won't lose any resolution.

Quote:

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Originally Posted by MARAD75

Hi,
Can anyone suggest an 8 pin flash chip that can take an analog voltage between, say 0 - 1 volts and out put a proportionally higher analog voltage, based on the math I will do in the code. Thanks for the help!
Ron

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Hi, Ron

I think the math will drive the need for codespace ... so ... what are those Top Secret Math calculations ???

Some OPA also are to consider for a simple LINEAR conversion ...

8 pins 12F683 ( thanks to Russ) will give you 2 k Words ,ADCs and a PWM unit ... and you won't find bigger ( say ... as a PIC ...)

Alain

Hi Alain, and all others,
Thanks for the help. Been using an LM358 and it works well. I just thought if there was a pic that would do it, then I can get fancy with the code math until I find what works best. I will probably try a 12F683, play with the A/D and see what I get.
Thanks all,
Ron

The PIC will work, but the linearity and accuracy will be less than if you use an op amp.