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nader
Joined: 29 Aug 2004 Posts: 12
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need a cost efficient 8 bit DAC |
Posted: Wed May 18, 2005 9:24 am |
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could some one guide me for selecting a cost efficient 8 bit DAC
that needed single power supply. |
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kender
Joined: 09 Aug 2004 Posts: 768 Location: Silicon Valley
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Posted: Wed May 18, 2005 10:25 am |
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My favorite is MAX517/MAX518. Single/dual channel, I2C interface.
If you want something really cost efficient, you could run PWM output into an RC filter. It will make a poor man's DAC. However, this approach is a lot less precise. |
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DragonPIC
Joined: 11 Nov 2003 Posts: 118
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Posted: Wed May 18, 2005 12:25 pm |
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kender wrote: |
If you want something really cost efficient, you could run PWM output into an RC filter. It will make a poor man's DAC. However, this approach is a lot less precise. |
and monitor it with an ADC channel. _________________ -Matt |
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kender
Joined: 09 Aug 2004 Posts: 768 Location: Silicon Valley
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Posted: Thu May 19, 2005 3:09 am |
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Quote: | and monitor it with an ADC channel. |
DragonPIC,
Could you post the code, which runs this closed loop?
Thanks,
Nick |
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DragonPIC
Joined: 11 Nov 2003 Posts: 118
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Posted: Thu May 19, 2005 12:40 pm |
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I guess I could scronge up the code I created for out HV PS. This was done on a small 12F675 and isn't the way I would do it on a larger PIC (with a PWM), so it wouldn't make such a good example. It pulses a switching circuit and the resulting voltage is read back from a voltage divider. The ripple is kept to a minimum by a cap. and the fact that I can vary how often I pulse it by reading the result back with the ADC.
Also, not my design so I wouldn't feel right posting the code. _________________ -Matt |
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