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art
Joined: 21 May 2015 Posts: 181
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16 bits ADC driver (TC500 microchip) |
Posted: Sun Jan 12, 2020 8:40 pm |
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Hi
I would like to know , where can i get 16 bits ADC driver for Microchip TC500.
I'm using PIC18F4550. Based on example EX_AD12.C it use 12bit ADC IC. How to change it to 16 bit ADC ? Is there any 16 bit ADC example to work with ? Please help me. |
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PCM programmer
Joined: 06 Sep 2003 Posts: 21708
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Posted: Sun Jan 12, 2020 10:35 pm |
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The TC500 doesn't have an i2c or SPI interface. Why do you want to use this chip ?
What device makes the analog voltage that you want to read ? |
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art
Joined: 21 May 2015 Posts: 181
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Posted: Sun Jan 12, 2020 11:18 pm |
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Actually i do not know what kind of16 bits ADC ic that i can use with EX_AD12.C example. Could you give a suggestion? I would prefer to use a DIL package. |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19378
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Posted: Sun Jan 12, 2020 11:41 pm |
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Haven't got the compiler in front of me at the moment, so can't check that
example. However I'd have thought that this used one of the 12bit PIC's.
Something like 80% of newer PIC's have 12bit ADC's. So the PIC16F18424
and all it's brethren, and on the PIC18's, chips like the 47K22. There are
literally hundreds of PIC models with this. Almost anything launched in
the last couple of years.
However, one caveat, a couple of the early ones have huge 'errata' on
these ADC's, so be careful and read the errata sheet before you buy. |
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art
Joined: 21 May 2015 Posts: 181
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Posted: Mon Jan 13, 2020 12:03 am |
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Hi,
I've decided to used MAX1416 as 16 bit ADC. If I refer to EX_AD12.C example, it used 12 bit ADC MCP3208.
Both IC have almost identical pin out, which have CLK,DOUT,DIN and CS. However I don't have MAX1416 driver.
The question here is, is it possible to use EX_AD12.C example with MAX1416 by modifying MCP3208.c and change it to MAX1416.c ? My final target is to read 16 bit ADC using PIC18F4550. |
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temtronic
Joined: 01 Jul 2010 Posts: 9177 Location: Greensville,Ontario
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Posted: Mon Jan 13, 2020 5:55 am |
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Actually the driver is the EASIEST part of the project ! Getting reliable 16 bit data is the REAL challenge. You'll have to read and follow the datasheet about PCB design, traces, bypass caps, power feed, etc. and even then you WILL have problems. Be prepared to spend 1-2 months MINIMUM on getting 'OK' 14 bit data. 3-4 PCB designs with several additional components..
Getting high bit ADC to work is 1/2 proper design, 1/2 magic and 1/2 shear luck !!
In the late '70s I design/build 16 bit PMT interfaces in very high EMI locations( aka Optical emission spectrometers).NO amount of book reading had the answers....eventually I got very reliable 15 bits though.
Jay |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19378
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Posted: Mon Jan 13, 2020 7:06 am |
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The actual ADC driver is loaded as a separate item.
#include <ltc1298.c>
You would need to change this to the right driver for your ADC chip. make
sure it's functions are compatible (or write ones if not).
Agree wholeheartedly with Jay. People don't realise just how good the
ground, board layout, and supplies need to be to genuinely get 16bit
performance. When you get down here 'routine' things like op-amps
(and even resistors!), get noisy. I use some sensors that have signals
changing by fractions of a uV, and getting these to give reliable readings
without too much noise is a combination involving thought/care at every
stage.... |
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