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funkydude
02-08-2005, 11:42 PM
hey,i need an A to D, and then a D to A converter. Has anyone done that before? I need it for communication.
What chip would be nice? I want the whole thing to be portable.

Thankss

jack
02-09-2005, 06:57 PM
Do you think information provided by you is sufficient for anybody to pick out a right converter for you? No clues.....nothing!!

ice
02-09-2005, 08:59 PM
I normally use TI's serial DACs and ADC's .
They are very easy interface and require no extra components at all .
You clock in 8 cycles and the IC responds by giving 8 bits out

Ive interfaced the TLC549 8 bit ADC with a PIC16F84a to get voltage readings from a temperature sensor.
The codes and schematics can be found here in my temperature controller project
http://www.machinegrid.com/content/view/51/108/

RI also mirrors it here
http://www.roboticsindia.com/modules.php?name=News&file=article&sid=81&mode=&order=0&thold=0


I just finished implementing the TLC1549 DAC .I'll put put the schema/codes when i get the time

Vivek
02-11-2005, 03:40 PM
ADC -
For beginners I would reccomend
ADC0809
Rs 135 types i guess

8 bit, and parallel output. just single pin control.
simple to interface after you read the datasheet
(search analog devices website) or also explained in Gaonkar i guess.
a popular 8085 cpu book in engineering.

DAC -
it depends on how mouch you can spend and would like to work.
Gerrys idea of using a TI dac is good.
my suggested chips my cost rs 1000+ so i wont suggest an IC.

low resolution dac can be made by a simple op-amp and some resistors.

OR

if you know how to generate PWM using the MCU you are plannig to use,
you can feed the PWM to a simple RC low-Pass-filter (1 R and 1 C, Re 1)
and the output would be analog voltage proportional to the duty-cycle of the PWM.
the PWM frequency should be aleast 10 times the time constant of RC (R*C)
this method requires only 1pin from your cpu, and almost not software.

cheers!
Vivek

Vivek
02-11-2005, 03:42 PM
oops - search ADC0809 at national semiconductor

02-12-2005, 08:59 AM
Thanks vivek,ice! I appreciate your help

funkydude
02-12-2005, 09:00 AM
Oops,i had forgotten to sign in last time.Thanks guys

funkydude
02-12-2005, 09:02 AM
Hey jack, i guess you were right, but ice and vivek are just brilliant :)

itechfreak
12-29-2009, 11:57 AM
There are few people who like to share whatever they know.

Thanks ice and vivek

akshay66
12-29-2009, 01:16 PM
Can you please tell me what are you trying to make??

Regards Akshay,

GayleShier
02-05-2014, 05:40 PM
there is nothing wrong in putting forth whatever the good you have and if it is helping anyone then so far so good